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Wavelength division or frequency division (e.g., Raman, Brillouin, etc.)

Subclass of:

398 - Optical communications

398043000 - MULTIPLEX

Patent class list (only not empty are listed)

Deeper subclasses:

Class / Patent application numberDescriptionNumber of patent applications / Date published
398082000 By optical coupling 115
398081000 Dispersion compensation 59
398091000 Different sources 19
398093000 Including feedback 11
398097000 Repeater 8
398089000 Multiple Access (e.g., WDMA) 7
398096000 Through free space 6
398090000 Electrically controlled single source 2
20120183297METHOD AND DEVICE FOR ADJUSTING A LASER IN AN OPTICAL NETWORK - A method and a device for adjusting a laser in an optical network. At least one alive message is transmitted from a first optical component towards a second optical component. A confirmation message is transmitted from the second optical component to the first optical component determining the wavelength of the laser to be used based on the alive message received by the second optical component. Furthermore, an optical communication system is provided with an optical element.07-19-2012
20100086308ELECTRO-OPTIC CONVERSION MODULE, OPTIC-ELECTRO CONVERSION MODULE AND CONVERSION METHODS THEREOF - An electro-optic conversion module (04-08-2010
Entries
DocumentTitleDate
20130028605SERIALLY-DISTRIBUTED ACCESS POINTS IN A COMMUNICATION NETWORK - Serially-distributed access points in a communication network include a cable including network communication wires, a plurality of access points connected in series with the network communication wires along a length of the cable, and a headend interface connected at one end of the cable and operable to provide a communication interface with the access points. Low-cost access point chipsets are used to build an enterprise-class communication network by embedding many low-cost, consumer grade access point chipsets into a single cable. The distance between the chipsets is small enough so as to create many microcells.01-31-2013
20090196615DISPERSION MAPPING OF TRANSMITTED CHANNELS IN A WDM SYSTEM - Chromatic dispersion is determined based on the arrival times of different frames of data in a wavelength division multiplexed (WDM) system having an optical communication link. Namely, a first frame is transmitted on a first optical channel, which is supplied to the optical communication link. A second frame is then transmitted on a second optical channel and the transmission time difference between the two frames is obtained. At a receive end, the difference in arrival times of the two frames is measured to obtain a relative time delay between the first and second frames. The relative time delay is the sum of the transmission time difference and the propagation time difference (the time difference attributable to chromatic dispersion) between the two frames. Thus, by subtracting the transmission time difference from the relative time delay, the propagation time difference can be obtained. The chromatic dispersion in units of picoseconds/nm can be obtained by dividing the propagation time difference by the difference in wavelength between the first and second optical channels.08-06-2009
20100150561OPTICAL RECEIVER, OPTICAL LINE TERMINAL AND METHOD OF RECOVERING RECEIVED SIGNALS - An optical receiver is provided which can be applied to a wavelength division multiplexing passive optical network (WDM PON) based on a reflective semiconductor optical amplifier employing a wavelength reuse scheme. The optical receiver includes a photo diode to convert an optical signal to an electrical signal; a pre-amplifier to linearly amplify the electrical signal and convert the amplified electrical signal to a voltage signal; a post-amplifier, which is equipped with a gain control function, to convert the voltage signal to a signal with a constant output level and to control a decision threshold of the converted signal; and an offset voltage generator to generate a predetermined offset voltage for the decision threshold control of the post-amplifier and to provide the offset voltage to the post-amplifier. Accordingly, it is possible to increase an extinction ratio of a downstream optical signal to a predetermined level in the WDM PON based on a reflective semiconductor optical amplifier employing a wavelength reuse scheme, and it is possible to reduce an optical power, which is received by the reflective semiconductor optical amplifier incorporated in a subscriber terminal, below a predetermined level. As a result, it is possible to improve transmission quality of the downstream and upstream optical signals.06-17-2010
20100150560APPARATUS AND METHOD FOR TRANSMITTING OPTICAL SIGNALS WITH ENHANCED REFLECTION SENSITIVITY IN WAVELENGTH DIVISION MULTIPLEXING PASSIVE OPTICAL NETWORK (WDM-PON) - Disclosed are an optical transmission apparatus and method in a wavelength division multiplexing passive optical network (WDM-PON). The optical transmission apparatus outputs an optical signal by applying a DC bias current and an RF signal to a laser diode at a threshold current level of the laser diode, thereby broadening an optical spectrum of the laser diode. Accordingly, an optical link becomes less vulnerable to reflection induced noise, which contributes to improve stability and reliability of the optical link.06-17-2010
20100150559Time-interleaved polarization-division-multiplexed transmission systems and transmitters - A WDM system having at least two channels, each of which employs two polarizations, is arranged so that the start times of symbols carried by one polarization of a channel are displaced in time from the start times of symbols carried by the other polarization of that channel, e.g., the start time for each symbol on one polarization is not substantially synchronized with the closest-in-time symbol start time on the other polarization of that channel. Preferably, the data signals are modulated using a return-to-zero (RZ) format and the start times of the symbols of the data signal carried by one polarization of a channel is offset from the start time of the symbols data signal carried by the other polarization of that channel by between 20% to 80%—preferably 50%—of the symbol period of the data signals, when the data signals have the same symbol period.06-17-2010
20100150558Dynamic wavelength service over a roadm optical network - A system and method for dynamically adding/dropping wavelengths in a reconfigurable optical add-drop multiplexer (ROADM) transport network to form a wave division multiplexing virtual private network is disclosed. The system includes at least one optical transponder, a plurality of optical fan-out devices, each arranged to receive an input signal from a network degree and coupled to at least one of a plurality of optical fan-in devices, each optical fan-in device arranged to output a signal to a network degree, the optical fan-out devices comprising at least one wavelength selective switch and the optical fan-in devices comprising at least one wavelength selective switch, the optical fan-out devices and optical fan-in devices being connected so as to enable signals input from each of the plurality of network degrees to be switched to another network degree of the plurality of network degrees; a plurality of demultiplexers for locally dropping selected wavelengths; a plurality of multiplexers for locally adding selected wavelengths; and at least one customer-dedicated fiber switch interposed between the at least one optical transponder and the plurality of demultiplexers and multiplexers. The fiber switch is coupled to wavelengths and degrees that are allocated for a bandwidth-on-demand application. Other configurations include additional fan-in and fan-out devices interposed between a mux/demux assembly and the optical transponders to support wavelength redistribution applications.06-17-2010
20110188860ELECTRICAL EQUALIZING PROCESSING METHOD AND DEVICE FOR OPTICAL SIGNAL AND OPTICAL FIBER COMMUNICATION SYSTEM - The electrical equalizing processing method for optical signal includes the following steps. An input optical signal is split into N channels of optical signals, in which N is an integer greater or equal to 2; band-pass filtering is performed on the split N channels of optical signals, in which central frequencies of a frequency band used in the performing of band-pass filtering on the N channels of optical signals are not exactly the same, and a passband of the frequency band and a frequency spectrum range of the N channels of optical signals overlap; the N channels of optical signals on which band-pass filtering is performed are converted into corresponding N channels of an analog electrical signal; an electrical equalizing process is performed on the N channels of the analog electrical signal to output an optical signal electrical equalizing processing result.08-04-2011
20090190928METHOD AND ARRANGEMENT FOR SWITCHING A RAMAN PUMP LASER ON AND/OR OFF - Optoelectrical conversion of the received optical service signal (OSS), bandpass filtering and subsequent squaring produce a spectral line at the clock frequency (f07-30-2009
20080292316Method and Apparatus for Reducing Crosstalk in a DWDM Transmission System - A method and apparatus is provided for transmitting a WDM optical signal. The method begins by modulating a plurality of optical channels that are each located at a different wavelength from one another with a respective one of a plurality of information-bearing electrical signals The channel spacings between adjacent ones of the plurality of optical channels are selected such that the optical channels give rise to selected FWM terms that lie outside a channel bandwidth of the optical channels. Each of the modulated optical channels is multiplexed to form a WDM optical signal. The WDM optical signal is then forwarded onto an optical transmission path.11-27-2008
20100158530SYSTEM AND METHOD FOR PERFORMING HIGH-SPEED COMMUNICATIONS OVER FIBER OPTICAL NETWORKS - Processing a received optical signal in an optical communication network includes equalizing a received optical signal to provide an equalized signal, demodulating the equalized signal according to an m-ary modulation format to provide a demodulated signal, decoding the demodulated signal according to an inner code to provide an inner-decoded signal, and decoding the inner-decoded signal according to an outer code. Other aspects include other features such as equalizing an optical channel including storing channel characteristics for the optical channel associated with a client, loading the stored channel characteristics during a waiting period between bursts on the channel, and equalizing a received burst from the client using the loaded channel characteristics.06-24-2010
20100119229METHOD AND SYSTEM FOR MULTIPLEXER WAVEGUIDE COUPLING - An optical device for optically multiplexing or demultiplexing light of different predetermined wavelengths is provided, the optical device comprising at least one first waveguide (05-13-2010
20100074623THREE-WAY HANDSHAKE (3WHS) OPTICAL NETWORK SIGNALING PROTOCOL - A method for optical network signaling processing of a signal from a first node to an end node through intermediate nodes is presented. The method comprises determining, in a first pass from the first node to the end node, available wavelengths and wavelength conversion at each node, the end node optimizing wavelengths using the available wavelengths and wavelength conversions, at each node, dropping a cross-connect command, in a second pass from the end node to the first node, choosing wavelengths for connection based on the optimizing step, in a third pass from the first node to the end node, receiving at each node a signal message and releasing unused cross-connect commands, the end node identifying the chosen wavelengths and releasing the unused resources, and transmitting the signal on the chosen wavelengths. Restoration paths can also be determined. Optimizing can include selecting and marking one or more backup wavelengths.03-25-2010
20130034357BIDIRECTIONAL OPTICAL TRANSMISSION AND RECEIVING DEVICE - There is provided a bi-directional optical transmitting and receiving apparatus. The bi-directional optical transmitting and receiving apparatus includes: a package having a cavity and allowing a plurality of lead wires to pass therethrough; a platform mounted on the package and including a through hole formed above the cavity and having sloped surfaces; a reception unit mounted within the cavity and generating an electrical signal corresponding to input light made incident to the cavity through the through hole and outputting the generated electrical signal to at least one of the plurality of lead wires; a transmission unit mounted on the platform and generating output light according to an electrical signal transmitted through at least one of the plurality of lead wires; and a wavelength division multiplexing (WDM) filter mounted on the platform to transfer the output light toward an optical fiber and the input light toward the through hole.02-07-2013
20120207477OPTICAL TRANSMISSION DEVICE AND OPTICAL FILTER CIRCUIT - There is provided an optical transmission device, the optical transmission device including a wavelength selective switch configured to select a first optical signal having a first wavelength from an input signal of wavelength division multiplexing, an optical filter circuit configured to include an optical tunable filter having a pass wavelength that is tunable to a second wavelength of a second optical signal for passing therethrough, a splitter configured to split the input signal, a split signal split by the splitter being transferred to the optical filter circuit, and a coupler configured to couple the first optical signal selected by the wavelength selective switch and the second optical signal passed through the optical filter circuit.08-16-2012
20100098422OPTICAL COMMUNICATION APPARATUS AND METHOD OF CONTROLLING SEMICONDUCTOR OPTICAL AMPLIFIER - An optical communication system and method thereof include outputting a wavelength division multiplexed (WDM) light to a transmission line, the WDM light being multiplexed from a plurality of signal lights, and one of the plurality of signal lights being converted from a pilot superimposed signal that has a data signal superimposed with a pilot signal and receiving the WDM light at a receiving station including a demultiplexer, a semiconductor optical amplifier, a photoelectric converter, a detection unit, and a controller. The plurality of signal lights are demultiplexed into a plurality of electric signals, respectively and the pilot signal is detected in the plurality of electric signals, with the exception of the pilot superimposed signal, and an amplification condition of the semiconductor optical amplifier is controlled based on the pilot signal detected.04-22-2010
20130039661ECHELLE GRATING WITH CYCLIC FREE-SPECTRAL RANGE - An optical de-multiplexer (de-MUX) that includes an optical device that images and diffracts an optical signal using a reflective geometry is described, where a free spectral range (FSR) of the optical device associated with a given diffraction order abuts FSRs associated with adjacent diffraction orders. Moreover, the channel spacings within diffraction orders and between adjacent diffraction orders are equal to the predefined channel spacing associated with the optical signal. As a consequence, the optical device has a comb-filter output spectrum, which reduces a tuning energy of the optical device by eliminating spectral gaps between diffraction orders of the optical device.02-14-2013
20090285577Optical Frontend for Integration of Optical and Wireless Networks - Data is transmitted by radio over fiber in a wavelength division multiplex optical transmission system. Data is transmitted over a single optical channel by directly modulating a single wavelength laser with a baseband data signal. Multiple single wavelength laser beams are multiplexed into a single multi-wavelength laser beam. All of the single optical channels are up-converted to RF frequencies by modulating the intensity of the multi-wavelength laser beam with an RF carrier.11-19-2009
20090154929GAIN EQUALIZER, OPTICAL AMPLIFIER, LOSS COMPENSATION METHOD, AND OPTICAL AMPLIFICATION METHOD - A gain equalizer for compensation a variation of intensity among a plurality of optical signals each including a different wavelength in a wavelength multiplexed optical signal includes an input part for receiving the wavelength multiplexed optical signal, an outputting part and a gain equalizing unit for repeatedly giving a loss to the wavelength multiplexed optical signal received by the input part, and for outputting the wavelength multiplexed optical signal to the outputting part. Here, the loss is set for each wavelength and is smaller than a loss characteristic required for compensation the variation of intensity.06-18-2009
20090154928WAVELENGTH DIVISION MULTIPLEXER/DEMULTIPLEXER HAVING FLAT WAVELENGTH RESPONSE - Provided is a wavelength division multiplexer/demultiplexer having a flat wavelength response. In the wavelength division multiplexer/demultiplexer, a modified taper-shaped optical waveguide is interposed between an input waveguide and a first slab waveguide, such that the distribution of an optical signal input to an Arrayed Waveguide Grating (AWG) has a sinc-function shape. Thus, a flat wavelength response can be obtained in an output waveguide. In addition, the modified taper-shaped optical waveguide interposed to obtain a flat wavelength response has a small size and a simple structure, and thus can be applied to a conventional wavelength division multiplexer/demultiplexer without a design change.06-18-2009
20130084071Manual ROADM front panel configuration - With Reconfigurable Optical Add Drop Modules (ROADMs) gaining popularity in the fiber optic market, many network designers are seeing the benefits of this technology. But the industry standard has been to make ROADMs automatically configurable, which adds considerably to the cost. Significant savings can be achieved by creating a manual ROADM for locations that do not require frequent configuration changes. This is achieved using a unique front panel configuration of a simple Optical Add Drop Module (OADM) system.04-04-2013
20130084072OPTICAL RECEPTION APPARATUS AND OPTICAL NETWORK SYSTEM - An optical apparatus includes a dispersing medium configured to receive carrier light which has been subjected to phase modulation in accordance with subcarrier modulation signals which has been modulated using data signals, and a signal extractor configured to extract the data signals from light output from the dispersing medium.04-04-2013
20100092176POLARIZATION-DIVERSE, HETERODYNE OPTICAL RECEIVING SYSTEM - To provide a polarization-diverse, heterodyne optical receiving system, a light signal is transmitted into an optical fiber having a plurality of optical sensors that are distinguishable using a multiplexing arrangement. A return light signal from the optical fiber is mixed with an optical local oscillator light signal, where the mixing outputs plural output signal portions having different polarizations. A birefringence of a particular optical sensor is determined based on the plural signal portions.04-15-2010
20100092175REFLECTIVE SEMICONDUCTOR OPTICAL AMPLIFIER AND OPTICAL SIGNAL PROCESSING METHOD USING THE SAME - Provided are a semiconductor optical amplifier and an optical signal processing method using the same. The reflective semiconductor optical amplifier includes: an optical signal amplification region operating to allow a downward optical signal incident from the external to obtain a gain; and an optical signal modulation region connected to the optical signal amplification region and generating a modulated optical signal. The downward optical signal is amplified through a cross gain modulation using the modulated optical signal and is outputted as an upward optical signal.04-15-2010
20100142959Optical waveform shaping method and optical waveform shaping apparatus - In an optical waveform shaping apparatus, a WDM signal light is amplified by a first optical amplifier, and thereafter, is input to a first nonlinear medium; a spectrum of the signal light of each wavelength is expanded due to SPM in the first nonlinear medium to thereby separate a signal component and a noise component; and for each spectrum, only a signal component on a short wavelength side is collectively extracted by an optical filter. Then, an output light of the optical filter is amplified by a second optical amplifier, and thereafter, is input to a second nonlinear medium, and the wavelength of each signal light is collectively shifted to a longer wavelength side due to self-frequency shifting in the second nonlinear medium, to thereby return the wavelength of each signal light to that for when each signal light contained in the WDM signal light has been input. As a result, the signal light of each wavelength contained in the WDM signal light can be collectively waveform shaped, and also, the wavelength of each signal light after waveform shaped can be precisely the same as that before waveform shaped.06-10-2010
20100142958OPTICAL RECEIVER FOR THE WDM SYSTEM AND METHOD TO CONTROL THE SAME - An optical receiver with a simplified arrangement able to compensate the optical loss of the transmission medium is disclosed. The optical receiver of the invention includes an SOA in the front end thereof, an optical de-multiplexer, and a plurality of receiver modules that receives de-multiplexed light. The optical gain of the SOA is adjusted based on the electrical signals output from respective optical modules. When the receiver modules show the output thereof in a preset range, the bias current is kept unchanged, while, one receiver module shows the output out of the range, the bias current is incremented or decremented. When one receiver module shows the output out of the absolute maximum/minimum, the bias current is forced to the initial value.06-10-2010
20100142960UPGRADING METHOD, SYSTEM AND APPARATUS OF LOW-DENSITY WAVELENGTH DIVISION MULTIPLEXING SYSTEM - An upgrading method, a system, and an apparatus of a low-density wavelength division multiplexing (WDM) system are provided. The method includes: detecting an output wavelength shift of a wavelength conversion unit, and adjusting an output wavelength of the wavelength conversion unit having the output wavelength shift higher than a threshold, so that the output wavelength shift of the wavelength conversion unit is lower than the threshold; adjusting an adjustable interleaved demultiplexer, until requirements for a demultiplexing parameter of a high-density WDM system are met. Thus, the problem that services are interrupted when a low-density MDM system is upgraded to a high-density MDM system is solved. A WDM system, and a wavelength multiplexing/demultiplexing apparatus and method are also provided.06-10-2010
20100142957COMMUNICATION NETWORK MANAGEMENT SYSTEM, WAVELENGTH-DIVISION MULTIPLEX APPARATUS, COMMUNICATION MANAGEMENT APPARATUS, COMMUNICATION NETWORK MANAGEMENT METHOD AND COMMUNICATION NETWORK MANAGEMENT PROGRAM - A communication network management system including a node apparatus 06-10-2010
20130089333PHOTONIC INTEGRATED TRANSMITTER - A photonic integrated circuit transmitter and a method for transmitting optical signals including a mode-locked laser diode generating a frequency comb optical signal and inputting said comb optical signal into a multiplexer/demultiplexer which demultiplexes said comb optical signal into a plurality of individual optical signals. A plurality of reflective modulators each receiving a respective one of said demultiplexed individual optical signals and modulating said received individual optical signal and reflecting the modulated optical signal back to the multiplexer/demultiplexer. The multiplexer/demultiplexer then multiplexes the received modulated optical signal into a multiplexed output optical signal.04-11-2013
20090041462Optical Band Splitter/Combiner Device Comprising a Three-Arms Interferometer - A three-arm-Mach-Zehnder interferometer for splitting/combining a first and a second wavelength band, wherein the optical device includes: a first and second optical splitting/combining element; a differential optical delay device comprising a first, a second and a third optical path; each of the first and second optical splitting/combining elements, is of the (25-50-25%)λx(0-0-100%)λy type, wherein λx is a wavelength with the first optical band and λy is a wavelength with the second optical band, and the first, second and third optical paths of the differential optical delay device are configured to introduce, at a wavelength λz within the first optical band, a phase delay Δφ of 2πm.02-12-2009
20090080893Multi-band hybrid SOA-RAMAN amplifier for CWDM - A multi-band hybrid amplifier is disclosed for use in optical fiber systems. The amplifier uses Raman laser pumps and semiconductor optical amplifiers in series to produce a relatively level gain across the frequency range of interest. Multiple Raman pumps are multiplexed before coupling into the fiber. The Raman amplified optical signal may be demultiplexed and separately amplified by the SOAs before re-multiplexing. Gain profiles of the Raman pumps and the SOAs are selected to compensate for gain tilt and to alleviate the power penalty due to cross-gain modulation in the SOAs. The disclosed hybrid amplifier is especially useful in coarse wavelength division multiplexing (CWDM) systems.03-26-2009
20100129079OPTICAL WDM TRANSMISSION APPARATUS AND OPTICAL WDM TRANSMISSION METHOD - An optical WDM transmission apparatus includes plural optical attenuators that respectively attenuate the power of optical signals separated according to wavelength; plural first optical receivers that respectively detect the power of the attenuated optical signals; a multiplexer that multiplexes the optical signals; a second optical receiver that detects the power of the multiplexed optical signal; and a monitoring control unit that includes a first control system that controls the optical attenuators so that the powers detected at the first optical receivers respectively become target values, and a second control system that, based on the power detected by the second optical receiver and information concerning the number of wavelengths corresponding to the optical signals input, controls the optical attenuators so that the powers of the optical signals respectively become the target values.05-27-2010
20110008052Port Wavelength Restriction Encoding in Wavelength Switched Optical Network - An apparatus comprising a path computation element (PCE) coupled to a path computation client (PCC) and configured to perform a path computation using port wavelength restriction information for a network element (NE), wherein the port wavelength restriction information is encoded and received in a port wavelength restriction Type-Length-Value (TLV) that comprises a matrix identifier (ID), a restriction type, and the port wavelength restriction information. Also disclosed is a network component comprising at least one processor coupled to a memory and configured to receive a port wavelength restriction information TLV that corresponds to a NE, and obtain a restriction type and port wavelength restriction information based on the restriction type from the port wavelength restriction TLV, and use the port wavelength restriction information to calculate a path for the NE.01-13-2011
20130071122OPTICAL COMMUNICATION SYSTEM, OPTICAL RECEIVER, OPTICAL TRANSPONDER, WAVELENGTH MULTIPLEXING OPTICAL COMMUNICATION SYSTEM, WAVELENGTH MULTIPLEXING RECEIVING DEVICE, AND WAVELENGTH MULTIPLEXING OPTICAL TRANSPONDER - To reduce PAPR in an optical OFDM communication system, light is phase-modulated by a base-band OFDM signal which is the output of a transmission signal processing unit 03-21-2013
20130071121WAVELENGTH-DIVISION MULTIPLEXING FOR USE IN MULTI-CHIP SYSTEMS - Embodiments of a system that includes an array of chip modules (CMs) is described. In this system, a given CM in the array includes a semiconductor die that is configured to communicate data signals with one or more adjacent CMs through electromagnetic proximity communication using proximity connectors. Note that the proximity connectors are proximate to a surface of the semiconductor die. Moreover, the given CM is configured to communicate optical signals with other CMs through an optical signal path using optical communication, and the optical signals are encoded using wavelength-division multiplexing (WDM).03-21-2013
20090092391METHOD AND SYSTEM FOR POWER STABILITY CONTROL IN WAVELENGTH DIVISION MULTIPLEXING NETWORKS - Methods and systems for controlling power fluctuations in a network including a plurality of nodes are disclosed. A node in the network may be configured to modify power levels in accordance with either an active state or an inactive state. The node may transition to an inactive state in response to a power change that exceeds a power change threshold. The role of the node in controlling the power fluctuation in the network is reduced in the inactive state.04-09-2009
20090092394Orthogonal Frequency Division Multiple Access Based Virtual Passive Optical Network (VPON) - Various types of passive optical networks operate simultaneously in one passive optical network system comprising an optical line terminal, a passive remote node, and multiple optical network units. Downstream data is orthogonal frequency division multiplexed onto a single wavelength optical carrier transmitted on a primary downstream optical beam from the optical line terminal to a splitter in the passive remote node. The primary downstream optical beam is split into multiple secondary downstream optical beams; each is transmitted to a specific optical network unit. Upstream data is orthogonal frequency division multiplexed onto a single wavelength optical carrier transmitted on a secondary upstream optical beam from each optical network unit to a coupler in the passive remote node. The upstream wavelength for each optical network unit is different. The wavelength division multiplexed optical beam is transmitted from the passive remote node to a parallel signal detector in the optical line terminal.04-09-2009
20090092392VIRTUAL I/Q MULTIPLEXING IN OPTICAL CODE DIVISION FOR SECURE LOCAL AREA OFDM - A system and method for virtual I/Q multiplexing in optical code division for secure local area OFDM includes encoding a wide spectrum signal, which includes a plurality of spectral bins, to provide a complementary spectral coding over at least two channels. The complementary spectral codings are intensity modulated with opposite polarity for each channel. An M-ary Orthogonal Frequency Division Multiplexing (OFDM) signal is modulated using the complementary spectral codings of opposite polarity with separate complementary spectral encoded (CSE) optical codes to provide a virtual in-phase (I) and quadrature (Q) (I/Q) multiplexing for the OFDM signal.04-09-2009
20120308235Integrated Commercial Communications Network Using Radio Frequency and Free Space Optical Data Communication - A stabilized ultra-high bandwidth capacity transceiver system that combines an E-band (71-76 GHz, 81-86 GHz) millimeter wave RF transceiver with an eye-safe adaptive optics Free Space Optical (FSO) transceiver as a combined apparatus for simultaneous point-to-point commercial communications. The apparatus has a high degree of assured carrier availability under stressing environmental conditions. The apparatus establishes and maintains pointing and stabilization of mmW RF and FSO optical beams between adjacent line of sight apparatuses. The apparatus can rapidly acquire and reacquire the FSO optical carrier link in the event the optical carrier link is impaired due to adverse weather.12-06-2012
20110013911HIGH-SPEED OPTICAL TRANSPONDER SYSTEMS - The present disclosure provides high-speed wavelength division multiplexing (WDM) transponders (e.g., 10 Gb/s, 40 Gb/s, 100 Gb/s, and beyond) that receive one or more optical signals and convert and/or remodulate the received optical signals onto a newly generated optical channel along with overhead processing/addition, forward error correction, and the like. In general, the transponders of the present invention include a client-side and a line-side, each with bi-directional optical transmission. The transponders provide an effective mechanism to support WDM networks that are transparent to the client-side.01-20-2011
20110013910Wavelength real time display on the equipment for WDM optical networking systems with wavelength tunable capability - A wavelength tunable device for use in a wavelength division multiplexing (WDM) system comprising a display device for displaying at least one operating wavelength of the wavelength tunable device. The display device is electrically coupled to a control unit in the wavelength tunable device so as to display the tuned wavelength in real time. The wavelength tunable device may be, in exemplary embodiments, an optical transponder, wavelength division demultiplexer, or wavelength division multiplexer. In embodiments where the optical equipment has a plurality of tunable ports, the display device is adapted to display the operating wavelength of each tunable port.01-20-2011
20090290876Light Receiver, Optical Communication System and Method - A receiver includes wavelength demultiplexer for demultiplexing a received WDM light into light signals at respective central frequencies thereof, delay interferometer for converting a light signal output from wavelength demultiplexer into an intensity signal, and light detector for converting an output signal from delay interferometer into an electric signal. The interval between interferential frequencies of delay interferometer is 2/(2n+1) times the interval between the central frequencies of the WDM light. Logic inverting circuit outputs the output signal from the light detector while non-inverting or inverting the logic level thereof depending on the received central frequency.11-26-2009
20090290878Generating an Optical OFDM Signal with Reduced OSNR Requirement - A method for generating an optical OFDM signal with reduced optical signal to nose ratio requirement includes separating an up-converted OFDM signal into a first part and a second part out of phase with the first part; driving a modulator with the first and second parts of the of the up-converted OFDM signal; and varying a lightwave with the modulator for generating a carrier suppressed OFDM signal having improved receiver sensitivity.11-26-2009
20090269068TRANSMISSION SYSTEM - A wavelength division multiplexing transmission system, the system comprising: a plurality of channels at different wavelengths, each channel comprising a transmitter, a receiver, and one or more amplifiers, the system further comprising an encoder for encoding data with a coding, and; a decoder for decoding transmitted data; prioritizing means for prioritizing the data on each channel; monitoring means for monitoring directly or indirectly, raw (uncorrected) bit errors on each channel; power adjusting means for, varying the power on a channel in response to the bit error rate.10-29-2009
20090269067BI-DIRECTION OPTICAL MODULE INSTALLING LIGHT-EMITTING DEVICE AND LIGHT-RECEIVING DEVICE IN SIGNAL PACKAGE - A bi-directional optical module with an improved optical crosstalk between the transmitter unit and the receiver unit is disclosed. The optical module provides the LD, the PD, the WDM filter secured with the block, and the package with the co-axial shape. The block provides a slant surface, where the WDM filter is secured thereon, the bottom surface facing the PD mounted on the package, and an aperture connecting the slant surface and the bottom surface. The PD is enclosed within a space formed by the bottom surface and the primary surface, which electrically and optically isolates the PD from the LD.10-29-2009
20090269066Single-Unit Integrated Transceiver Having Pump Source and Transceiver Module Using the Same - Provided are a sing-unit integrated transceiver having a pump source and a transceiver module using the transceiver. The single-unit integrated transceiver includes: an optical transmitter converting an input electric signal into a downstream optical signal; an optical receiver converting a received upstream optical signal into an electric signal; the pump source amplifying the downstream or upstream optical signal using a gain medium positioned in an optical transmission line to amplify an output optical signal; a convergence unit arranging or converging the downstream and upstream optical signals to/from the optical transmission line; and a multiplexing and/or a demultiplexing filter, the multiplexing filter positioned on an optical path between the optical transmitter/pump source and the convergence unit, and multiplexing the downstream optical signal and the amplified optical signal to pass to the convergence unit, the demultiplexing filter positioned on an optical path between the convergence unit and the optical receiver and demultiplexing the upstream optical signal to pass to the optical receiver.10-29-2009
20090269065Setting Up A Circuit In A Network - In particular embodiments, setting up a circuit in a network includes establishing by control plane logic that planning pre-conditions for planning a circuit have been satisfied, and initiating the planning of the circuit. The control plane logic establishes that reservation pre-conditions for reservation of a resources for the circuit have been satisfied and initiates the reservation of the resources for the circuit. The control plane logic establishes that activation pre-conditions for activation of the circuit have been satisfied and initiates the activation of the circuit.10-29-2009
20090074416Communication Systems - A transmitter transmits signals on multiple channels, and they are wavelength multiplexed according to Coherent WDM. Quality of the received signals is very much enhanced by the transmitter tuning the relative phases of neighbouring channels according to delay characteristics of the optical path. In one example, the transmitter adds a relative delay of ¼ bit period between each data signal and the beat frequency signal for the odd and even channel groups, to counter the receiver side delays introduced by the AMZI. This corresponds to aligning the transmitter such that the eye crossing corresponds to a minimum of the 80 GHz beat signal. In order to obtain a stable phase relationship between adjacent channels the 80 GHz tone is set to a particular value. Any harmonics or sub-harmonics will similarly vary with phase and therefore can also be used as an error signal for a phase stabilisation circuit. The phase stabilisation circuit in the transmitter therefore can maintain a desired stable optimum phase alignment between neighbouring channels.03-19-2009
20120224855DIGITAL PHASE CONJUGATION FOR FIBER-OPTIC LINKS - An optical phase conjugator that can be deployed within a long-haul fiber-optic link of an optical WDM system to improve the system's tolerance to intra- and inter-channel nonlinear effects. In one embodiment, the optical phase conjugator has a digital signal processor configured to perform, in the digital electrical domain, a phase-conjugation transformation for various components of a WDM signal so that certain signal distortions imposed on that signal in the front portion of the fiber-optic link are reduced in the back portion of the link. Advantageously, the optical phase conjugator is flexibly configurable to employ an input-to-output carrier-frequency-mapping configuration that is most beneficial under particular operating conditions.09-06-2012
20130064546PHOTONIC COMMUNICATIONS DEVICE WITH AN FM/PM DISCRIMINATOR AND RELATED METHODS - A communications device includes a transmitter device having first and second optical sources and generating respective first and second modulated optical carrier signals at first and second optical carrier frequencies based upon an input signal. The communications device also includes an optical waveguide coupled to the transmitter device, and a receiver device coupled to the optical waveguide and including an FM-PM discriminator having a transfer function with a positive slope portion and a negative slope portion so that the first optical carrier frequency is positioned on the positive slope portion and the second optical carrier frequency is positioned on the negative slope portion.03-14-2013
20090238568Optical Shaping for Amplification in a Semiconductor Optical Amplifier - The present invention provides a system, apparatus, and method for efficient optical amplification and transmission of a data-encoded optical signal within a networking device, such as a transmitter or receiver. In various embodiments of the invention, an optical duobinary signal or hybrid duobinary signal is generated and shaped in preparation for amplification of the optical signal by an SOA. The deleterious impact of SOA fast gain dynamics may be reduced by taking advantage of characteristics of a duobinary or hybrid duobinary signal (e.g., a relatively lower pulse amplitude and no phase encoded data) and shaping the optical duobinary pulse (e.g., smoothing amplitude swings within the signal and spectral compression).09-24-2009
20090238569OPTICAL TRANSMISSION APPARATUS AND OPTICAL COMMUNICATION SYSTEM - An optical transmission apparatus is provided with an optical filter on a transmission line between a reception end of a transmission line and an OSC receiver. The optical filter has transmission characteristics such as to pass main signal light and optical supervisory channel light (OSC light), and to cut off noise light contained in at least one end portion band on a short wavelength side and a long wavelength side of an OSC transmission band used for reception of OSC light. By such a configuration, even in a case where the OSC light is Raman amplified and transmitted, the influence of noise light due to Raman amplification can be reduced, and OSC light can be received reliably, enabling high dependability to be realized.09-24-2009
20090047021Integrated overlay card, optical line terminal and system with integrated overlay card, and methods for operating the system and terminal - An integrated overlay card, an optical line terminal with an integrated overlay card, and a method for operating an optical network. The integrated overlay card may fit at least partially within the optical line terminal. The integrated overlay card includes a wavelength dimension multiplexer/demultiplexer that overlays first signals at a first wavelength onto second signals at a second wavelength, so as to combine signals. The combined signals may be routed to an optical network. In example embodiments, the invention may be used to provide an IP television service.02-19-2009
20130163992MULTICARRIER BASED OPTICAL SIGNAL TRANSMITTING APPARATUS AND OPTICAL SIGNAL RECEIVING APPARATUS - Disclosed is an optical signal transmitting apparatus including: an optical carrier generator configured to generate a plurality of optical carriers and outputs the optical carriers to optical modulators corresponding to the optical carriers, respectively; a plurality of optical modulators configured to modulate the optical carriers, respectively, according to an input signal; and an optical combiner configured to couple a plurality of optical signals from the plurality of optical modulators.06-27-2013
20130163993DIRECTLY-COUPLED WAVELENGTH-TUNABLE EXTERNAL CAVITY LASER - Disclosed is a directly-coupled wavelength-tunable external cavity laser including a gain medium that generates an optical signal by an applied bias current; an optical waveguide structure that is coupled to the gain medium to form a minor surface and causes lasing in the mirror surface when the applied bias current has a threshold or higher; and a radio frequency transmission medium that adds a radio frequency signal to the applied bias current to adjust an operating speed of the optical signal.06-27-2013
20090196616WAVELENGTH DIVISION MULTIPLEXING MODULE - A telecommunications module includes an optical wavelength division multiplexer/demultiplexer configured to demultiplex a first optical signal input into the telecommunications module into a plurality of different wavelengths, a fiber optic splitter configured to split a second optical signal input into the telecommunication module into a plurality of optical signals, and a plurality of optical add/drop filters, each of the optical add/drop filters configured to combine one of the optical signals that has been split by the fiber optic splitter and one of the wavelengths that has been demultiplexed by the optical wavelength division multiplexer/demultiplexer into a combination output signal that is output from the telecommunications module.08-06-2009
20120237222Micro Free-Space WDM Device - Techniques for designing optical devices that can be manufactured in volume are disclosed. In an exemplary an optical assembly, to ensure that all collimators are on one side to facilitate efficient packaging, all collimators are positioned on both sides of a substrate. Thus one or more beam folding components are used to fold a light beam up and down through the collimators on top of the substrate and bottom of the substrate.09-20-2012
20090202247Optical multiplexing/demultiplexing device - In an optical multiplexing/demultiplexing device are arranged in parallel and disposed on a substrate. The optical multiplexing/demultiplexing device is disposed with three or more Mach-Zehnder interferometers between the first and second optical input/output ports. The optical multiplexing/demultiplexing device divides, by wavelength, multiplexed light comprising first light and second light whose wavelengths are different and which are input to one of the first optical input/output ports and outputs the multiplexed light from each of the second optical input/output ports. The absolute value of an optical path difference ΔL of each the Mach-Zehnder interferometers is constant. The optical multiplexing/demultiplexing device includes one or more each of a pair of two successive Mach-Zehnder interferometers where the sum of their optical path differences becomes +2 ΔL or −2 ΔL and a pair of two successive Mach-Zehnder interferometers where the sum of their optical path differences becomes 0.08-13-2009
20120219296METHODS AND SYSTEMS FOR COHERENT MULTI-SUBCARRIER SOURCE GENERATION - A method of generating a multi-subcarrier optical signal is disclosed. A local oscillator oscillates one or more data signals to generate one or more oscillating data signals. A series of modulators phase modulate a lightwave to generate a phase modulated lightwave, wherein the series of modulators are driven by the one or more oscillating data signals. The intensity modulator modulates the phase modulated lightwave, the intensity modulator being driven by one of the oscillating data signals, to generate the multi-subcarrier optical signal.08-30-2012
20090297152WDM PON PROTECTION SCHEME USING A DUAL PORT ARRAYED WAVEGUIDE GRATING (AWG) - A Wavelength Division Multiplexed Passive Optical Network (WDM-PON) includes an Optical Line Terminal (OLT) including a first Arrayed Waveguide Grating (AWG) MUX/DEMUX, and a remote node including a second AWG MUX/DEMUX. Each AWG MUX/DEMUX has at least two input ports for receiving a respective wavelength division multiplexed optical signal, and a plurality of output ports. Each output port of the Optical Line Terminal AWG MUX/DEMUX is coupled to a respective transceiver of the OLT. Each output port of the remote node AWG MUX/DEMUX is coupled to a respective PON having at least one optical network terminal (ONT). Respective first and second optical paths are coupled between corresponding input ports of the first and second AWG MUX/DEMUXs. Means are provided for sourcing seed light of the WDM-PON into a selected one the first and second optical paths.12-03-2009
20110280580TECHNIQUE FOR TRAFFIC RECOVERY IN MULTILAYER COMMUNICATION NETWORKS - A method for recovery of a traffic flow being conducted via a communication line in a multi-layer communication network, the traffic flow comprising a Guaranteed traffic portion GT and a Best Effort traffic portion BET assigned to respective bandwidth resources of the line. The communication network comprising at least two network layers provided with respective traffic recovery mechanisms which utilize bandwidth resources such as time slots, wavelengths, physical links, logical links. The traffic flow may comprise traffic component(s) at different network layers, and the bandwidth resources of the traffic component(s) may be divided into GT and BET portions. The method comprises forming a shared pool of recovery resources, for all the layers in the line, from the bandwidth resources assigned to BET on all the layers. The method further comprises utilizing the shared pool of recovery resources for recovery of any of the traffic components of the traffic flow.11-17-2011
20080292317INTEGRATED MULTIPLEXER/DEMULTIPLEXER HAVING OFFSET TRANSMITTERS AND RECEIVERS FOR USE IN AN OPTICAL TRANSCEIVER MODULE - An apparatus for use in an optical transceiver module that incorporates an integrated multiplexer/demultiplexer for high speed data transfer applications. One example embodiment includes a transmissive block arranged to interface with a transmit optical port, a receive optical port, and a plurality of optical subassemblies. The transmit optical port may transmit a first multiplexed optical signal and the receive optical port may receive a second multiplexed optical signal. Filters may be positioned between the transmissive block and one or more of the optical subassemblies to transmit signals at predetermined wavelengths while reflecting other signals incident thereon.11-27-2008
20100329681Multimode Optical Amplifier As A Receiver Pre-Amplifier For Free-Space Optical Communications - In the method for processing a signal light from free-space by amplifying said signal for free-space optical communications, wherein the improvement includes the steps of (a) pre-amplifying said signal light with low noise; and (b) coupling said signal light into a multimode filter which reduces coupling losses compared to single mode filters.12-30-2010
20100266285OPTICAL FIBRE NETWORK - An optical fibre network comprises a laser source (10-21-2010
20110142450USE OF PRE-VALIDATED PATHS IN A WDM NETWORK - Various example embodiments are disclosed. According to an example embodiment, a method may include receiving a resource request for optical resources within a wavelength division multiplexed (WDM) optical network; comparing one or more parameters of the resource request to a list of pre-validated paths for the WDM optical network, each pre-validated path identifying an optically feasible label switched path between a source node and a destination node; determining that there is a pre-validated path on the list that matches the one or more parameters of the optical resource request; and sending a message to request a reservation of resources along the matching pre-validated path.06-16-2011
20090310969Optical transmitting apparatus and optical multiplexing unit - Even during a protection period in which a state transition is not caused from an ALC state to an ALD state, when an output light level that is inputted is below a threshold for ALC transition read from a memory, a processor causes a transition by switching an internal state from an ALC state to an ALD state. Then, an ALD operation is started, outputting a control voltage to a VAT control unit so as to achieve a predetermined fixed attenuation amount.12-17-2009
20110280579ENERGY-EFFICIENT AND FAULT-TOLERANT RESONATOR-BASED MODULATION AND WAVELENGTH DIVISION MULTIPLEXING SYSTEMS - Systems and methods are provided for modulating, channels in dense wavelength division multiplexing (“DWDM”) systems. In one aspect, a modulation and wavelength division multiplexing system includes a channel source and a waveguide tree structure disposed on a substrate. The tree structure includes waveguides branching from a root waveguide. The waveguides include two or more terminus waveguides coupled to the channel source. The system also includes one or more modulator arrays disposed on the substrate. Each modulator array is optically coupled to one of the two or more terminus waveguides and is configured to modulate channels injected into a terminus waveguide from the channel source to produce corresponding optical signals that propagate from the terminus waveguide along one or more of the waveguides to the root waveguide.11-17-2011
20090324228ONT TEST UNIT - An Optical Network Terminal (ONT) simulator is provided. The ONT simulator includes one or more partially functional ONTs coupled to an Optical Line Termination (OLT) and an ONT/Optical network termination Management and Control Interface (ONT/OMCI) simulation utility. The ONTs receive test network traffic from the OLT and forward any OMCI traffic contained in the network traffic to the ONT/OMCI simulation utility. The ONT/OMCI simulation utility in turn simulates the operation of field-deployable ONT using the OMCI traffic.12-31-2009
20120106966TRANSPONDER POOL SIZING IN HIGHLY DYNAMIC TRANSLUCENT WDM OPTICAL NETWORKS - A system and method for sizing transponder pools in a dynamic wavelength division multiplexing optical network having selected nodes designated to have a shared transponder pool is presented. The method comprises performing network simulations, generating transponder pool histograms (for each node having a transponder pool) based on the network simulations, performing statistical analysis using the transponder pool histograms to determine probability distribution and distribution parameters for each node and to calculate the horizontal axis location that has a specified distribution tail area, sizing the transponder pools according to the horizontal axis location that has the desired distribution tail area, executing network call blocking simulations to calculate call blocking probabilities, determining whether the call blocking probabilities meet blocking requirements, when the blocking requirements are met, using the sized transponder pools, and when the blocking requirements are not met, adjusting the distribution tail area and repeating sizing, executing and determining steps.05-03-2012
20110293279Tunable Multi-Wavelength Optical Transmitter and Transceiver for Optical Communications Based on Wavelength Division Multiplexing - Techniques, devices and systems for optical communications based on wavelength division multiplexing (WDM) that use tunable multi-wavelength laser transmitter modules.12-01-2011
20110293281OPTICALLY VARIABLE FILTER ARRAY APPARATUS - In an optically variable filter array apparatus, WDM-signal light beams of m channels ranging in wavelength from λ12-01-2011
20110293280Control of an Interferometric Optical Polarization Beam Splitter - The present invention provides a system, apparatus and method to control an optical polarization beam splitter. A portion of an optical output of the polarization beam splitter is converted into a corresponding electrical signal. The electrical signal is then provided to the polarization beam splitter as a control signal via a feedback loop. The polarization beam splitter controls a characteristic of the optical output of the polarization beam splitter in response to the received control signal. The characteristic, for example, may be controlled through thermo-optically or electro-optically. The control system may be used over a period of time to maintain the characteristic at a desired value, for example as the components of the polarization beam splitter, or other elements used in the control of the polarization beam splitter, age.12-01-2011
20110008050Demultiplexing and Multiplexing Method and Apparatus - A method of demultiplexing client data from a constant bit rate (CBR) optical client serial link into lower bit-rate CBR signals for transmitting over a plurality of wavelength division multiplexed (WDM) optical channels. The method comprises mapping blocks of bytes from a client frame received from the optical client serial link into respective CBR transport frames for transmitting over the respective WDM optical channels and such that the number of bytes in the client frame is the same as the number of bytes in the plurality of respective CBR transport frames. Modifying a number of non-payload bytes from the client frame to carry CBR transport frame control data in each said CBR transport frame.01-13-2011
20100014861DUAL ASYNCHRONOUS MAPPING OF CLIENT SIGNALS OF ARBITRARY RATE - A network may include an ingress node that is configured to receive a client signal having a client rate that is one of a multiple different client rates, asynchronously map the client signal into a first frame of a first rate, asynchronously map the first frame into a second frame of a second rate, and output the second frame on the network; an intermediate node that is configured to receive the second frame, recover the first frame from the second frame, asynchronously map the first frame into a third frame of a third rate, and output the third frame on the network, where the intermediate node does not recover the client signal from the first frame; and an egress node that is configured to receive the third frame, recover the first frame from the third frame, recover the client signal from the first frame, and output the client signal.01-21-2010
20120189308OPTICAL SIGNAL-PROCESSING APPARATUS, RECEIVING APPARATUS, AND OPTICAL NETWORK SYSTEM - An optical modulator combines and inputs a signal light propagating through the optical network and a control light having information concerning the optical network to a nonlinear optical medium. The optical modulator modulates the signal light according to changes in intensity of the control light, in the nonlinear optical medium.07-26-2012
20090080891PASSIVE OPTICAL NETWORK SYSTEM AND RANGING METHOD - In a WDM-PON system wherein a plurality of ONUs transfer signals by sharing wavelengths, one wavelength dedicated to a ranging procedure is set, and the ranging is performed with only the dedicated wavelength, so as to measure reciprocating delay times. At the other wavelengths, transmission signals from a plurality of ONUs are transferred in time division multiplexing based on the obtained reciprocating delay times. An OLT includes a burst receiver circuit for only the wavelength dedicated to the ranging, and subsequently to the ranging, the OLT adjusts transmission amplitudes and transmission phases for the ONUs, so as to equalize received amplitudes and received phases in the OLT. For this purpose, the OLT includes means for measuring the amplitudes and phases of received signals, as the burst receiver circuit, and it includes a table for managing the received amplitudes and received phases of the respective ONUs.03-26-2009
20090028565Monitoring mechanisms for optical systems - This application describes optical monitoring devices and applications in optical systems for monitoring various optical parameters of light, including the signal to noise ratio, the degree of polarization, and the differential group delay (DGD).01-29-2009
20080310844Hybrid Optoelectronic Module - A hybrid optoelectronic module used in duplexer or triplexer includes a transmitter chip for emitting a first signal beam at wavelength λ12-18-2008
20100119230OPTICAL RECEIVING CIRCUIT - An optical receiving circuit receives and demodulates an optical signal subjected to phase modulation and wavelength division multiplexing. The optical receiving circuit includes an interfering unit that causes a reference signal to interfere with the optical signal to output resulting signals as positive-phase signals and negative-phase signals; and a wavelength separator having input ports receiving the positive-phase signals and the negative-phase signals, the positive-phase and negative-phase signals being adjacent to each other. The wavelength separator separates according to wavelength, the positive-phase signals and the negative-phase signals, and from output ports, outputs for each wavelength, a separated positive-phase signal and negative-phase signal in a state of being adjacent to each other. The optical receiving circuit further includes balanced receivers respectively provided for each wavelength, where a given balanced receiver for a given wavelength performs balanced reception and demodulation of the separated positive-phase signal and negative phase signal of the given wavelength.05-13-2010
20110150482Transmission control system, subscriber-side communication device, and office-side communication device - Provided is a subscriber-side communication device including a subscriber-side processing unit that continuously performs signal processing regardless of computer restart and includes a transmission processing unit that performs a data transmission process according to transmission control information contained in a received signal from the office-side communication device. Also provided is an office-side communication device including an office-side processing unit that continuously performs signal processing regardless of computer restart, and a transmission control information computing unit that computes transmission control information for each subscriber-side communication device, the office-side processing unit including a transmission control information storing unit that stores transmission control information of each subscriber-side communication device computed by the transmission control information computing unit, and a transmission control processing unit that performs a transmission control process with each subscriber-side communication device by using the transmission control information of each subscriber-side communication device stored in the transmission control information storing unit.06-23-2011
20120033974OPTICAL COMMUNICATION SYSTEM, OPTICAL COMMUNICATION APPARATUS, AND OPTICAL COMMUNICATION METHOD THEREOF - An optical communication system includes a first optical communication apparatus configured to insert a wavelength control signal in a main signal to produce a modified main signal; convert the modified main signal into a first optical signal; and transmit the first optical signal, and a second optical communication apparatus configured to receive the first optical signal; extract the wavelength control signal from the received first optical signal; determine a wavelength of a second optical signal based on the extracted wavelength control signal; and transmit the second optical signal to the first optical communication apparatus.02-09-2012
20090087185OPTICAL TRANSMISSION APPARATUS AND CONTROL METHOD THEREFOR - An optical transmission apparatus comprising a first detector for detecting the power of the supervisory signal light separated from received wavelength-division multiplexed signal lights; a second detector for detecting the power of the wavelength-division multiplexed signal lights after the separation of the supervisory signal light; a gain-controlled type optical amplifier for amplifying the wavelength-division multiplexed signal lights; an optical attenuator coupled to the amplifier; and a control unit for controlling the optical amplifier and the optical attenuator so as to keep the output level of the wavelength-division multiplexed signal lights to a predetermined target value, wherein the control unit restrains automatic output level control by the optical attenuator when the supervisory signal light power fluctuates within its permissible range and fluctuations in the signal light power have deviated from its permissible range.04-02-2009
20090087184Method, System And Apparatus For Distributing Node Information - A method for distributing node information, including an optical node generating an information bit stream based on its own node information and distributing the information bit stream it generates and a wavelength sequence corresponding to the node information. According to various embodiments, an information bit stream is generated based on the node information of an optical node so as to reduce the volume of data in the node information distributed by an optical node.04-02-2009
20090087183WAVELENGTH DIVISION MULTIPLEXING SERIAL VIDEO SIGNALS OVER OPTICAL INTERFACES USING THE XFP FORM FACTOR - Certain pins of an XFP connector are re-purposed to enable the connector to receive, for example, four 11.88 Gb/s serial data streams (for a receiver), or output four 11.88 Gb/s serial data streams (for a transmitter). The four data streams are wavelength division multiplexed inside the XFP module for transmission over a single optical fibre, providing a total interface capacity of 47.52 Gb/s. An XFP receiver module is defined to convert the WDM signal back to four 11.88 Gb/s serial data streams.04-02-2009
20100080561DIGITAL FRAMER ARCHITECTURE WITH A FRAMING MARKER - Embodiments of the present invention provide for diverse routing of a plurality of data streams, representative of a client signal of an unknown format, across multiple communication paths of a digital optical network through the use of a marker embedded in the client signal which is then inserted into the client payload portion of a transport frame. The multiple communication paths include different signal and path attributes related to the optical signals which transport the data streams across the digital optical network, as well as the physical structure of the digital optical network itself, all leading to timing variations in the multiple communication paths. The digital optical network transports the plurality of data streams in the form of wavelength division multiplexed signals, or banded wavelength division multiplexed signals.04-01-2010
20090297149Optical add/drop multiplexer - A disclosed optical add/drop multiplexing device demultiplexes a first signal into multiple signals according to wavelengths, drops one or more of the demultiplexed signals to a transponder, adds one or more signals output from the transponder, multiplexes these signals into a second signal, and outputs it. The device includes an injecting unit for injecting one of measurement signals, each of whose wavelength corresponds to that of a different demultiplexed signal, into a core of a multicore cable within the device, the core being used to transmit the different demultiplexed signal having the corresponding wavelength; a preventing unit for preventing the one measurement signal from emanating; a measuring unit for measuring, for each wavelength, levels of the one measurement signal before and after the corresponding core; a calculating unit for calculating loss of the corresponding core, based on the measured levels; and an informing unit for reporting the calculated loss.12-03-2009
20090142061Fiber optic communication system with automatic line shutdown/power reduction - A wavelength division multiplexing (WDM) fiber optic communication system is operative to transmit WDM signals between multiple nodes. Each of the nodes has a booster EDFA, and in-band (IB) and out-of-band (OB) supervisory channels operative to monitor the integrity of a transmission link by generating and detecting respective in-band and out-of-band control signals. The booster EDFA is operative to receive the multiplexed WDM and IB signals and generate an output signal carried by a plurality of fiber-optic cables between the nodes. The booster EDFA is operative to switch from an automatic gain control regime upon detecting of at least one of the IB and OB signals to an automatic power control regime upon loss of both IB and OB signals. The output signal of the EDFA in the AGC regime has a high power sufficient for being transmitted the WDM and IB signals, and has a low power in the APC regime sufficient for transmitting only the IB signal between the nodes.06-04-2009
20120106969Communications apparatus, multiplex communications apparatus, communications system, and communication method - A communications apparatus includes a transmitter that transmits signal light that is wavelength division multiplexed with other signal light and that is to be transmitted to an opposing apparatus, and a processor that is operative to change a frequency of the signal light to be transmitted by the transmitter based on detection results at the opposing apparatus and concerning variation in the frequency of the transmitted signal light.05-03-2012
20120106968OPTICAL TRANSMISSION APPARATUS - There is provided an optical transmission apparatus including: a transmitter to output an optical signal to be transferred to other optical transmission apparatus; a first dummy light source to generate first dummy light having a wavelength which is not included in an optical signal received from other optical transmission apparatus; a first wavelength-multiplexer to wavelength-multiplex the optical signal received from other optical transmission apparatus, the optical signal output from the transmitter, and an optical signal with a wavelength, of the first dummy light, which is not included in the optical signal received from other optical transmission apparatus and in the optical signal output from the transmitter; and an optical amplifier to amplify an optical signal multiplexed by the first wavelength-multiplexer.05-03-2012
20120106967METHOD AND DEVICE FOR SIGNAL PROCESSING AND COMMUNICATION SYSTEM COMPRISING SUCH DEVICE - A method and a device provide signal processing. The method contains the steps of separating a pilot signal from an analog signal, reducing or compensating a noise based on a local oscillator laser by demodulating the pilot signal, processing the demodulated pilot signal, and combining the processed demodulated pilot signal with the analog signal. Furthermore, a method for signal processing at a transmitter, according devices and a communication system are described.05-03-2012
20090092395Upgraded Optical Communication System with Increased Transmission Capacity and Method - A method for upgrading a wavelength division multiplex (WDM) optical communication system includes replacing an installed transmitter operable to transmit a data stream at a defined bit rate with a return-to-zero M-ary phased shift keying (RZ-mPSK) transmitter operable to transmit the data stream at the defined bit rate and at least one other data stream at the defined bit rate together in an RZ-mPSK signal having a combined bit rate at least double the defined bit rate and a symbol rate equal to the defined bit rate. An installed receiver operable to receive the data stream at the defined bit rate is replaced with an RZ-mPSK receiver operable to recover the data stream at the defined bit rate and the at least one other data stream at the defined bit rate from the RZ-mPSK signal.04-09-2009
20110200334Wavelength Adjusting Method, Apparatus, and System - A wavelength locking method, apparatus, and system are provided. The wavelength locking method includes modulating, by using scrambling signals with a same frequency and different phases, each one of a plurality of optical channel signals respectively; processing, by a combiner, a splitter, and a wavelength locker, the modulated optical signals, so as to acquire photoelectricity detector (PD) signals; performing phase discrimination on the PD signals to acquire wavelength information of the optical channels; determining different shift values corresponding to the different wavelength information; and adjusting wavelengths of the optical channels according to the corresponding shift values.08-18-2011
20090169212Optical transmission apparatus and optical communication system - An optical communication system, where in an optical transmission apparatus arranged on a transmission side of respective repeating sections, an OSC optical amplifier is provided on an OSC light optical path between from an OSC transmitter to a multiplexer, and the OSC optical amplifier is controlled so that the power of OSC light transmitted on the transmission path becomes a previously set target value. As a result the OSC light is amplified by a different amplifying device to that for the main signal lights at the time of transmission. Therefore even in the case where the span losses are large, OSC light can be reliably received by the optical transmission apparatus on the reception side.07-02-2009
20100086306DYNAMIC ROUTING OF OPTICAL SIGNALS IN OPTICAL NETWORKS - A method for dynamic routing an optical signal in an optical network is provided, including: executing a shortest-path algorithm receiving input concerning a source node, a destination node and the topology of the network, providing a shortest-path tree comprising nodes and arcs connecting the nodes, the shortest-path tree comprising branches along which an effective attenuation is no greater than a predetermined limit, each branch comprising an end node and each end node being associated with a corresponding set of wavelengths; checking, for each end node having no wavelength conversion resources and for each wavelength, if the end node is connected to at least another node external to the branch through the wavelength; excluding, for any end node if the result of the checking is negative for at least one wavelength, the at least one wavelength from the corresponding set of wavelengths, thus updating the topology; and re-executing the shortest-path algorithm.04-08-2010
20080240717Optical transmitter/receiver module - Efficient absorption of radio wave emission can be ensured from a high frequency signal processing circuit in an optical transmitter/receiver module. The optical transmitter/receiver module pluggable to a communication device includes a housing having openings on an anterior and a posterior ends; an optical connector disposed at the anterior opening; a photoelectric converting unit that converts a wavelength-division multiplexed optical signal, that is input from an optical transmission line connected to the optical connector, into an electric signal; and a high frequency circuit board that performs high frequency signal processing of an electric signal converted by the photoelectric converting unit, whereinat the posterior opening, a connecting terminal of the high frequency circuit board is formed so that it is pluggable to a mother board of a communication device, and wherein radio wave absorbers are arranged in spaces between the top/bottom surfaces of the high frequency circuit board and the housing.10-02-2008
20090110402Distributed Wavelength Assignment Using Signaling Protocols in Wavelength Switched Optical Networks - An apparatus comprising a first node configured to forward a wavelength assignment message to a second node, wherein the wavelength assignment message comprises a wavelength set type-length-value (TLV), a wavelength assignment method selection TLV, a supplemental wavelength assignment information TLV, a traffic parameter TLV, or combinations thereof. Also included is a network component comprising at least one processor configured to implement a method comprising obtaining a wavelength set data, a wavelength assignment method selection data, a supplemental wavelength assignment data, a traffic parameter data, or combinations thereof, and using at least one TLV to represent the obtained data. Also included is a method comprising obtaining a wavelength assignment information comprising a wavelength set, a supplemental wavelength assignment information, a wavelength assignment method selection, a traffic parameter, or combinations thereof, and forwarding the wavelength assignment information along a path.04-30-2009
20090279893ANALOG FINITE IMPULSE RESPONSE FILTER - According to one embodiment of the invention, a programmable finite impulse response (FIR) filter is implemented with differential isolation circuits to isolate parasitic capacitance from attenuating an output signal at both a first and second differential output terminals of the FIR filter. The FIR includes a track and hold circuit and a summing circuit that provides operational advantages to the FIR filter.11-12-2009
20090297150Optical transmission apparatus, optical interface device, and optical transmission method - When an XFP is plugged into an optical interface unit by live-line plugging, an external bias voltage higher than an internal bias voltage is kept applied to a CDR incorporated in the optical interface unit until the XFP starts up. This prevents exertion of a negative effect on the CDR.12-03-2009
20090279894TRIPLE WAVELENGTH BIDIRECTIONAL OPTICAL COMMUNICATION SYSTEM - A triple wavelength bidirectional optical communication system includes an optical fiber, a transmitter optical subassembly and a receiver optical subassembly. The transmitter optical subassembly includes a first filter, a dual wavelength laser device and a first detector device. The dual wavelength laser device emits a first and a second laser beam to the optical fiber. The first detector device receives a third laser beam emitted from the optical fiber and propagated via the first filter. The receiver optical subassembly includes a second filter, a transceiver device and a second detector device. The transceiver device emits the third laser beam propagated via the second filter and reached to the optical fiber and also receives the first laser beam emitted from the optical fiber and propagated via the second filter. The second detector device receives the second laser beam emitted from the second facet and propagated via the second filter.11-12-2009
20090290877Monitoring for High Speed OFDM Signal Transmission - A method includes coupling an optical signal upconverted to a higher frequency and a digital signal having a bit rate similar to that of a subchannel of the upconverted optical signal, and obtaining, responsive to the coupling, a transmission signal with an optical carrier frequency carrying the digital signal and subchannels about the optical carrier frequency carrying the upconverted optical signal, the bit rate of the optical carrier being similar to that of the subchannels. In a preferred embodiment, the coupling includes electrically power coupling the upconverted optical signal with the digital signal, and modulating the coupled optical carrier frequency carrying the digital signal and subchannels about the optical carrier frequency carrying the upconverted optical signal.11-26-2009
20090297148AUTOMATIC PRE-EMPHASIS - A system and method are provided for controlling the pre-emphasis applied to an optical signal, in which the output level of individual transmitters is controlled in order to reach a pre-defined desired value of a quality metric. Transmitters are able to adjust their output power without external control in such a way as to optimise the power distribution across the system.12-03-2009
20100111535WDM SYSTEMS AND METHODS - A WDM optical system includes first and second WDM's including an optical link therebetween. Each WDM includes circuitry for linking multiplexer and demultiplexer circuitry to a plurality of modular elements. The modular elements include a first set of modules for converting between native protocol media signals and common format signals. A second set of modules converts between the common format signals and optical signals at separate wavelengths for communication with the multiplexers and demultiplexers. A dual path transmit and receive optical link is provided between near and far end WDM's.05-06-2010
20100278536METHOD AND APPARATUS FOR SUB-CARRIER FREQUENCY CONTROL - The invention pertains to methods, apparatus, and systems for controlling the sub-carrier frequencies in an optical frequency division multiplex communication system by using a metric available from the sub-carrier modem's digital receive block as an indicator of cross-talk between sub-carriers and adjusting the sub-carrier frequency separation as a function of that metric.11-04-2010
20120294617Virtual Network Control Method and System Based on Fluctuations - A virtual network control method, for adaptively controlling a topology of a virtual network formed on a physical network in response to environmental changes in the virtual network, is provided with: a step of storing the Langevin equation, as a fluctuation equation, which models the dynamics of the topology of the virtual network as a variable for controlling the number of wavelength paths on the physical network; a step of designing control parameters included in the fluctuation equation; and a step of controlling the topology of the virtual network by applying the control parameters to the fluctuation equation to change an order parameter included in the fluctuation equation when environmental changes occur in the virtual network, and by transitioning the solution of the fluctuation equation between attractors determined by the deterministic term of the fluctuation equation due to the fluctuation term of the fluctuation equation.11-22-2012
20120294616OPTICAL COMMUNICATION SYSTEM, OPTICAL TRANSMITTER, OPTICAL RECEIVER, AND OPTICAL TRANSPONDER - A sinusoidal wave output from an RF oscillator provided in a transmitter is phase-modulated using a baseband OFDM signal output from a transmitter-signal processing unit 11-22-2012
20100284694OPTICAL TRANSMISSION SYSTEM AND REPEATER - A repeater includes a variable optical attenuating unit that collectively attenuates WDM optical signal input, an optical-attenuation adjusting unit that adjusts attenuation in the variable optical attenuating unit, and an optical amplifying unit that collectively amplifies and outputs the WDM optical signal collectively attenuated, to a downstream side. An optical-attenuation adjusting unit includes an input level detector; an output level detector; an output-level transmitting unit that receives information of a signal level of WDM optical signal output by a repeater at an upstream side and transmits information of a signal level of the WDM optical signal detected by the output level detector to a repeater at a downstream side; and an attenuation amount controller that controls the variable optical attenuating unit by calculating an attenuation amount thereof based on information of a signal level detected by the input level detector and a signal level received by the output-level transmitting unit.11-11-2010
20100135662METHOD FOR THE RAMAN AMPLIFICATION OF OPTICAL SIGNALS AND TRANSMISSION SYSTEM - A system and method for Raman amplification of optical signals in a wavelength division multiplexing (WDM) optical transmission system includes transmitting optical signals within a transmission band via an optical waveguide between a transmitter and a receiver, Raman-amplifying the optical signals with at least one pump so as to distort an amplification profile of the Raman amplification within the transmission band, and rectifying the distorted amplification profile so as to compensate for the distortion.06-03-2010
20100129078OPTICAL TRANSMISSION SYSTEMS, DEVICES, AND METHODS - Optical communications systems including grooming, protection, restoration, and migration on a unified network platform, and using a unified control plane. The systems may include combinations of optical bypass and mesh restoration, may include combinations of shared mesh and dedicate protection, and may be combinations of long haul, extended long haul, and ultra long haul systems. The systems may also include a configurable DWDM tier to accommodate dynamic traffic patterns, thereby allowing for increased operational flexibility.05-27-2010
20080292318Optical transmission device,optical transmission method, and recording medium thereof - An optical transmission device that is installed at a node of a network and that performs transmission of an optical signal transmits the optical signal to an optical transmission device at the next node without amplifying the optical signal. The optical transmission device generates an adjustment optical signal used by a reception-side optical amplifier in the optical transmission device at the next node to adjust gain for a transmission loss of the optical signal. At the time of booting of the optical transmission device, the optical transmission device transmits the generated adjustment optical signal to the reception-side optical amplifier in the optical transmission device at the next node. Upon receiving a gain-adjustment-completion signal for notifying completion of gain adjustment using the adjustment optical signal from the reception-side optical amplifier, the optical transmission device controls the transmission of the adjustment optical signal to be stopped.11-27-2008
20080304830PASSIVE OPTICAL NETWORK, EQUIPMENT AND METHOD FOR SUPPORTING MULTICAST SERVICE - A Wavelength Division Multiplexed Passive Optical Network (WDM-PON), an Optical Line Terminal, an Optical Network Unit, a multiplexer/demultiplexer, and a method for realizing multicast service in the WDM-PON are disclosed. The WDM-PON and the method for realizing multicast service according to the present invention can transmit multicast service to be multicasted or broadcasted using a single wavelength, and thus the bandwidth resource of the system can be effectively saved and complexity of the system can be reduced.12-11-2008
20080304829WAVELENGTH MULTIPLEX TRANSMISSION APPARATUS, CONTROL METHOD, AND CONTROL PROGRAM - A wavelength multiplex transmission apparatus including a divided wavelength band unit which controls signal light in each of a plurality of divided wavelength bands into which a transmission wavelength band on a transmission path is divided, a light source which is provided in the divided wavelength band unit and outputs dummy light, and a control unit which controls power of a divided band multiplexed light, which is multiplexed light of the signal light and the dummy light, to have predetermined level by controlling the power of dummy light.12-11-2008
20110008051OPTICAL COMMUNICATION APPARATUS AND OPTICAL WAVELENGTH MULTIPLEXING TRANSMISSION SYSTEM - In case of a disconnection failure of an optical transmission line, a Raman amplifier generates a loss of main and supervisory signal alarms, an optical amplifier generates a loss of main signal alarm, and a supervisory signal transmission and reception unit detects the loss of supervisory signal. On the other hand, in case of a failure generated in an optical fiber, the supervisory signal transmission and reception unit performs APR control. Thus the optical amplifier stops outputting the main signal and continues to output the supervisory signal. The Raman amplifier generates the loss of main signal alarm, and the supervisory signal transmission and reception unit detects the loss of supervisory signal. The monitoring unit identifies failure point according to a combination of an existence of the loss of signal alarm by the Raman and optical amplifiers and the loss of supervisor signal by the supervisory signal transmission and reception unit.01-13-2011
20110008049TRANSMISSION APPARATUS, TRANSMISSION CONTROLLING METHOD, AND OPTICAL SUPERVISORY CHANNEL (OSC) PROCESSING APPARATUS - An integrated transmission apparatus includes a plurality of optical supervisory channel (OSC) processing units for processing OSC signals contained in a wavelength division multiplexing (WDM) signal received from a WDM network and a switching unit for performing the path control of synchronous digital hierarchy (SDH) frames. An OSC processing unit transmits the SDH frame, containing wavelength information indicated by, to the switching unit. Another OSC processing unit acquires the SDH frame, containing wavelength information, from the switching unit and sets an OSC signal which is to be appended to the WDM signal to be transmitted, based on the wavelength information.01-13-2011
20110222858OPTICAL COMMUNICATION APPARATUS AND OPTICAL COMMUNICATION METHOD - A present invention provides an optical communication apparatus and method which can use a data modulator and an OFDM modulator more narrow band than a transmission band.09-15-2011
20080212967WDM Systems and Methods - A WDM optical system including a media converter module including a plurality of converter cards, each converter card being configured to convert a native signal into an optical signal. The system also includes a panel bracket having an opening and a plurality of fingers, and a cable management panel including a drawer having an interior space. The cable management panel includes a splitter/combiner module mounted in the interior space, and the cable management panel is positioned in the opening of the panel bracket so that a space is defined between the cable management panel and the media converter module.09-04-2008
20100142956Method and Apparatus for Reshaping a Channel Signal - Higher rate channels (e.g., 40 Giga bits or greater) have large bandwidths and are susceptible to inter-channel crosstalk. Optical tunable filters may be used to overcome crosstalk. Tunable filters do not maintain their central wavelength over a long duration or a wide temperature range. An example embodiment of the present invention relates to shaping a channel signal within a dense wavelength division multiplexing signal and may employ a tunable filter and input and output optical power detectors to measure a modulated source channel signal at an input of the tunable filter and a filtered modulated source channel signal at an output of the tunable filter. A controller is configured to adjust a center wavelength of the tunable filter as a function of a difference between measurements of optical power by the optical power detectors. Adjusting the center wavelength shapes the channel signal and overcomes undesired effects for higher rate channels.06-10-2010
20090162066Intra-Channel Equalizing Optical Interleaver - An apparatus includes an interleaver configuration for at least one of combining or separating odd and even channel groups to achieve channel density doubling; and an optical equalizer for suppressing inter symbol interference within the channels to provide intra-channel equalizing in the optical path, the equalizer being integrated into the interleaver. Preferably, optical equalizer and interleaver are integrated together as a single monolithic device, the optical equalizer includes a passband that has a dip in the channel center to achieve a raised-cosine filtering profile in the optical signal path to achieve inter-symbol interference ISI suppression, and the equalizer includes integration into the optical path of the interleaver to realize a monolithic device combining or separating odd and even channel groups to achieve channel density doubling. Preferably, also, the optical equalizer includes a first equalizer with half the depth of required ripple dips at both a first output port and an input port and a second equalizer with half the depth of required ripple dips at a second output port.06-25-2009
20090162067OPTICAL TRANSMISSION DEVICE - An optical apparatus includes a first optical amplifier for adjusting an output value to a constant level; an optical signal processor located before the first optical amplifier and processing the optical signal; a second optical amplifier located before the optical signal processor and subjected to automatic gain control for adjusting a gain constant; and a controller detecting a level of the optical signal at an output of the second optical amplifier. The controller adjusts a level of an output value of the first optical amplifier such that the level of the optical signal at the output of the second optical amplifier is held at the optimum value if the detected level of the optical signal differs from an optimum value, compensates for a loss caused in the optical signal processor and maintains the level of the optical signal at the output of the second optical amplifier at the optimum value.06-25-2009
20110268446PROVIDING DIGITAL DATA SERVICES IN OPTICAL FIBER-BASED DISTRIBUTED RADIO FREQUENCY (RF) COMMUNICATIONS SYSTEMS, AND RELATED COMPONENTS AND METHODS - Optical fiber-based distributed communications systems that provide and support both RF communication services and digital data services are disclosed herein. The RF communication services and digital data services can be distributed over optical fiber to client devices, such as remote antenna units for example. In certain embodiments, digital data services can be distributed over optical fiber separate from optical fiber distributing RF communication services. In other embodiments, digital data services can be distributed over common optical fiber with RF communication services. For example, digital data services can be distributed over common optical fiber with RF communication services at different wavelengths through wavelength-division multiplexing (WDM) and/or at different frequencies through frequency-division multiplexing (FDM). Power distributed in the optical fiber-based distributed communications system to provide power to remote antenna units can also be accessed to provide power to digital data service components.11-03-2011
20090129779MULTIPLEX DELAY UNIT - According to one embodiment, a multiplex delay unit comprises an optical all-pass filter (OAPF) adapted to apply continuously tunable group delay to a wavelength division multiplexing (WDM) signal so that all of its WDM components are delayed by substantially the same delay time. The OAPF has a free spectral range (FSR) that matches spectral separation between carrier wavelengths of the WDM signal. Advantageously, an optical multiplex synchronizer suitable for feeding a synchronous optical switch fabric can be implemented as an integrated waveguide circuit using a plurality of such multiplex delay units.05-21-2009
20120070150Greedy Channel Selection Procedure for the Routing, Wavelength Assignment and Spectrum Allocation in the Flexible Optical WDM Networks - The inventive method, implemented in an optical flexible wavelength division multiplexing FWDM network, includes finding a connection route in an optical FWDM network on which a channel with sufficient spectrum is available at lowest wavelength among all available channels, finding K channels at first available K lower wavelengths out of available channels for minimizing total required spectrum; and selecting a channel which is routed through minimum number of optical fiber paths out of the K available channels at one of the lower wavelengths.03-22-2012
20110222859Compact Multiplexer/Demultiplexer - The present invention relates to a multiplexer/demultiplexer with a connection for inputting and/or outputting an optical signal which has signal components of different wavelengths, a carrier plate (09-15-2011
20090016726OPTICAL WAVELENGTH MULTIPLEXING ACCESS SYSTEM - According to the present invention, a star-type wavelength multiplexed communication network using optical TX/RX devices capable of assigning the wavelengths can be provided without using the monitoring light. In an embodiment of the present invention, an optical TX/RX device for transmitting and receiving a wavelength-multiplexed signal light comprises an optical receiver capable of varying the RX wavelength and an optical transmitter capable of varying the TX wavelength. The optical TX/RX device detects RX wavelengths not in use via the optical receiver, and assigns the RX wavelength of the optical receiver to one of the RX wavelengths not-in-use, and assigns the TX wavelength of the optical transmitter to a TX wavelength corresponding to the RX wavelength according to a correspondence table of TX and RX wavelengths in the memory. Then, the optical TX/RX device transmits a signal light on this TX wavelength, and detects the response on the RX wavelength. If the response is detected, communication is initiated using the assigned TX wavelength and the RX wavelength. If the response is not detected, the operation is repeated from the detection of RX wavelengths not in use to the transmission of the signal light on TX wavelength again.01-15-2009
20090052898Optical transceiver with a plurality of optical subassemblies electrically connected by integrated FPC board with a substrate - The present invention provides an optical transceiver with a function of the wavelength division multiplexing. The transceiver includes a receiver optical unit, a transmitter optical units and a substrate. Both optical unit includes a plurality of receiver optical subassemblies (ROSAs) or a plurality of transmitter optical subassemblies (TOSAs) and a plurality of wavelength selective filters. The ROSAs or the TOSAs in respective optical units is electrically connected with the circuit on the substrate by the flexible printed circuit (FPC) board with a plurality of branches, each connected to the ROSAs or the TOSAs, and a connecting portion fixed to the substrate.02-26-2009
20090016724Multimode optical transmission system and multimode optical transmission method - Provided is a multimode optical transmission system capable of reducing an influence of multimode dispersion occurring when an optical signal is transmitted in multimode. Light sources (01-15-2009
20090080892NETWORK APPARATUS AND METHOD FOR GUARANTEEING ROLE OF OPTICAL SUPERVISORY CHANNEL - A network node and method for guaranteeing the role of an optical supervisory channel (OSC) in an optical transport network (OTN) are provided. In the network node, at least two OSC units are multiplexed, one of the OSC units is set as a main unit, the other OSC unit is set as an auxiliary unit; and the auxiliary unit is activated when the main unit cannot be operated. Thereby, the network node can guarantee the stable role of the OSC.03-26-2009
20130216232OPTICAL TRANSMISSION APPARATUSES, METHODS, AND SYSTEMS - Apparatuses, systems, and methods are disclosed that provide for an agile coherent optical modem that can generate agile RF waveforms and data rates on a generic opto-electronic hardware platform. An “agile coherent optical modem” [ACOM] approach to optical communications by employing a software configurable and adaptive technologies to the transport system. The ACOM generate agile RF waveforms and data rates on a generic opto-electronic hardware platform. By employing advanced communication techniques to the optical domain such as wavelength agility, waveform agility, and symbol rate agility, it is possible to enable robust optical communications. The ACOM allows for the transport capacity of a communications link to be varied, thereby accommodating variations in transport conditions, range, opacity, etc.08-22-2013
20090097849PERFORMANCE OPTIMIZED RECEIVER WITH BANDWIDTH ADAPTIVE OPTICAL FILTER FOR HIGH SPEED LONG HAUL WDM SYSTEMS - The present invention provides a performance optimized receiver with a bandwidth adaptive optical filter for high speed long haul wavelength division multiplexed systems, such as 40 Gb/s and 100 Gb/s wavelength division multiplexed systems. The performance optimized receiver includes: a bandwidth and wavelength tunable optical filter, wherein the bandwidth and wavelength tunable optical filter is operable for receiving a plurality of wavelengths associated with a wavelength division multiplexed signal and passing one or more selected wavelengths, and wherein the bandwidth and wavelength tunable optical filter is operable for adjusting the bandwidth of each of the one or more selected wavelengths; and a receiver coupled to the bandwidth and wavelength tunable optical filter. Preferably, the receiver includes one or more of a bit error rate monitoring module and a signal quality monitoring module operable for monitoring the one or more selected wavelengths and providing feedback to the bandwidth and wavelength tunable optical filter such that the bandwidth and wavelength tunable optical filter adaptively adjusts the bandwidth of each of the one or more selected wavelengths.04-16-2009
20090232503OPTICAL TRANSCEIVER WITH OPTICAL MULTIPLEXER ON A FLEXIBLE SUBSTRATE - An optical transceiver for converting and coupling an information-containing electrical signal with an optical fiber including an optical fiber coiled over at least a portion of its length; a support element disposed in the transceiver module; a substrate for securing said coiled optical fiber to said support element to enable said coiled fiber to bend from a first direction to a second opposite direction inside said transceiver module; and an optical multiplexer secured to said substrate for receiving first and second optical fibers and multiplexing respective optical signals on said first and second optical fibers into a multi-wavelength beam onto a third optical fiber.09-17-2009
20110222855Wavelength division multiplexing-passive optical network system - The present invention proposes a wavelength division multiplexing-passive optical network (WDM-PON) system which transmits downstream data to an optical network unit (ONU) as an optical line termination (OLT) receives seed light from a spectrum-sliced external light source module. One characteristic of the proposed WDM-PON system is that optical transmitters of the OLT and ONU are operated regardless of optical wavelength. Another characteristic of the proposed WDM-PON system is that a conventional TDMA-PON (E-PON or G-PON) ONU can be accommodated without a change.09-15-2011
20110222857REMOTE NODE FOR WAVELENGTH-DIVISION-MULTIPLEXED PASSIVE OPTICAL NETWORK - A remote node for a wavelength-division-multiplexed passive optical network (WDM PON). The remote node comprises means for receiving uplink optical signals from one or more optical network units of the WDM PON; a broadband reflector for reflecting a self-seeding portion of the respective uplink optical signals to the respective uplink light sources; and wherein the reflector comprises a gain medium and is configured for receiving a pump optical signal from a central office of the WDM PON for amplifying the self seeding portion of the respective uplink optical signal.09-15-2011
20110229140WDM-PON SYSTEM, ONT, OLT AND METHOD FOR INITIALIZATION OF TUNABLE LASER - A wavelength-multiplexed passive optical network (WDM-PON) and a method are described herein for setting-up (e.g., wavelength tuning, power tuning) an ONT laser by establishing a communications channel on an optical layer between an optical line terminal (OLT) and an optical network termination (ONT). The communications channel is established by utilizing the OLT's laser shutdown function and the ONT's signal detection function.09-22-2011
20110229139TRANSPARENT FIBER CHANNEL LINK MANAGEMENT FOR PROTOCOL TRANSPORT - Methods and apparatus for providing distance extension and other transport functions such as error monitoring, provisioning, and link/service management in a fiber channel path are disclosed. According to one aspect of the present invention, a transport node includes a processing arrangement and an output interface. The processing arrangement creates a first ordered set that includes information associated with an ability for the transport node to receive a first fiber channel frame, and inserts the first ordered set between a second ordered set and a third ordered set of a fiber channel stream. The output interface transmits the fiber channel stream, which includes the information regarding whether the transport node is capable of receiving the first fiber channel frame.09-22-2011
20110229138Optical-signal processing apparatus, optical transmission method, receiver, and optical network system - In an optical network system: control light is generated by optical modulation based on a modulated data signal which is generated by modulation of a carrier signal with a data signal; and the control light is optically combined with an optical carrier which is to propagate through a nonlinear optical medium, so as to cause cross phase modulation of the optical carrier with the control light in the nonlinear optical medium.09-22-2011
20090175623OPTICAL SIGNAL DETECTOR - An optical signal detector is provided that detects an optical signal from an optical source using a plurality of optical sensors having different wavelength selectivities, thereby determining the peak wavelength of the optical signal and measuring the power of an optical signal corresponding to the peak wavelength. According to the optical signal detector, separate optical filters are not required and space and costs attributable to the installation of the optical filters can be saved, and thus there are effects in that the overall size and manufacturing costs of the device can be reduced.07-09-2009
20090003829DWDM HYBRID PON LT CONFIGURATION - A method, a system, and an optical transceiver board for use in a Passive Optical Network (PON), comprising a line terminal (LT) card comprising a plurality of transmitters and one receiver, a Dense Wave Division Multiplex (DWDM) combiner, wherein the LT card is communicably coupled to the DWDM combiner, and a broadband wavelength division multiplexer (WDM) communicably coupled to the DWDM combiner.01-01-2009
20090116838Bi-directional optical module with a polarization independent optical isolator - The present invention provides a bi-directional optical module with an optical isolator to prevent stray light from entering the laser diode (LD). The module includes a distributed feedback LD (DFB-LD), a photodiode (PD), a wavelength division multiplexed (WDM) filter, and a polarization independent isolator placed between the WDM filter and the optical fiber. The stray light emitted from the LD and scattered by optically discontinuous interface is prevented from returning to the LD by the isolator. Although the isolator shifts the optical axis of the receiving optical signal emitted from the optical fiber, the PD with a wide optical sensitive surface may receive almost whole portion of the receiving optical signal.05-07-2009
20090220234Optical Waveband Demultiplexer, Optical Waveband Multiplexer, and Optical Waveband Selective Switch - A simple optical waveband multiplexer/demultiplexer operable to separate a wavelength-division multiplexed light beam WDM consisting of a plurality of wavebands WB each including a plurality of optical channels, into a predetermined plurality of wavebands WB, and output the separated plurality of wavebands WB from a plurality of output ports, wherein the wavelength-division multiplexed light beam WDM is transmitted through two array waveguides each capable of performing a demultiplexing function with a resolution corresponding to wavelengths of the optical channels, and a characteristic of sequentially shifting the output ports by one position with shifting of input ports by one position, whereby the wavelength-division multiplexed light beam WDM is separated into a plurality of wavebands WB each including the mutually different optical channels selected from the optical channels included in the wavelength-division multiplexed light beam WDM, and the separated wavebands WB are outputted from the plurality of output ports, respectively.09-03-2009
20090245799PROTECTED LIGHT SOURCE FOR MULTIPLE WAVELENGTH DIVISION MULTIPLEXED PASSIVE OPTICAL NETWORKS (WDM-PONS) - A protected light source for generating seed light for at least two wavelength division multiplexed passive optical networks (WDM-PONs). The protected light source includes an optical coupler having N≧2 input ports and M≧2 output ports, each output port being optically connected to supply seed light to a respective set of one or more WDM-PONs. A respective multi-wavelength light source (MWLS) is optically coupled to supply seed light to each input port of the optical coupler. A controller unit controls operation of each multi-wavelength light source (MWLS).10-01-2009
20090220236MULTIDROP COMMUNICATIONS SYSTEM USING WAVE DIVISION MULTIPLEXING - A multidrop communications system for transferring data to a plurality of devices, comprises an optical fibre having first and second ends, a plurality of light sources for producing light of different respective wavelengths, modulation means to modulate light from each light source to encode respective data thereon, the modulation means outputting a plurality of modulated light components having said respective wavelengths, an optical multiplexer for multiplexing said modulated light components onto said first end of the optical fibre using wavelength division multiplexing, an optical demultiplexer connected to the second end of the optical fibre for demultiplexing light therefrom into a plurality of components having respective wavelengths, demodulation means for demodulating each of said components to extract said respective data, and means for transferring the extracted data to different respective target devices.09-03-2009
20090220238METHOD, DEVICE AND COMMUNICATION EQUIPMENT FOR CONTROLLING A BURST ASSEMBLY - A method for controlling burst assembly, device, and communication equipment thereof are provided. In the present invention, an assembly time and a predetermined time threshold are compared to determine a load change in a cache queue. If the load is increased or decreased suddenly, a length threshold is directly increased or decreased. If the load is to be increased, the length threshold is randomly increased according to a certain probability. If the load is to be decreased, the length threshold is randomly decreased according to a certain probability. If the load is in a normal state, the length threshold is maintained. Therefore, the length threshold is dynamically adjusted with the load change. The method and device provided by the present invention ensure an end-to-end (E2E) delay of the services and optimize the network performance.09-03-2009
20090220235THREE-ARM DQPSK MODULATOR - A modulator is disclosed that includes three arms between a splitter portion and a coupler portion. The modulator typically requires at most a π/2 phase shift between constellation points. Accordingly, the modulator is more efficient and consumes less power.09-03-2009
20090116839OPTICAL TRANSMISSION SYSTEM AND SIGNAL SPEED CONVERTING APPARATUS - A signal speed converting apparatus to be connected to a WDM transmission end office, comprising a first interface connected to a first optical line group, a plurality of second interfaces connected to a second optical line group, and a speed converter. The first interface has a first framer for terminating a frame in a first format received from the first optical line group and outputting an information signal extracted from the received frames as a serial signal train or parallel signal trains. The speed converter converts the output signal from the first framer into transmission signal trains each including interleaved communication frame by cyclically distributing the output signal from the first framer to a plurality of internal lines. Each of the second interfaces has a second framer for converting the communication frame received from one of the internal lines into information frame in a second format to be transmitted to the second optical line group. Management information inserting units are located between the first and second interfaces in order to insert management information to be communicated with an opposite apparatus into the transmission signal trains on the internal lines.05-07-2009
20090220233Wavelength selective switch having distinct planes of operation - A wavelength selective switch utilizing aperture-shared optics and functionally distinct planes of operation that enables high fiber port counts, such as 1×41, and multiplicative expansion, such as to 1×83 or 1×145, by utilizing elements optimized for performance in one of the functionally distinct planes of operation without affecting the other plane.09-03-2009
20090245795HIGH CAPACITY TRANSMITTER IMPLEMENTED ON A PHOTONIC INTEGRATED CIRCUIT - A high capacity optical transmitter implemented on a photonic integrated circuit chip comprises a single light source which supplies a continuous wave having a particular wavelength to a plurality of modulators to form modulated optical information signals. A phase shifter is coupled to at least one of the modulators and is used to shift the phase of the corresponding modulated optical information signal associated with a particular modulator. A polarization beam combiner receives each of the modulated optical information signals from the modulators and the modulated optical information signal from the phase shifter and combines each of these signals to form a polarization multiplexed differential quadrature phase-shift keying signal. The light source, the plurality of modulators, the phase shifter and the polarization beam combiner are all integrated on the chip.10-01-2009
20090245796OPTICAL RECEIVER INCLUDING A FILTER ON A PLANAR LIGHTWAVE CIRCUIT - A planar lightwave circuit (PLC) includes a substrate, a tunable filter, a demultiplexer (DEMUX), and an optical processor each disposed on the substrate. The tunable filter is configured to filter at least one of a bandwidth or a wavelength of a Wavelength Division Multiplexed (WDM) optical input signal. The DEMUX is connected to the tunable filter and configured to receive a filtered WDM optical input signal at an input and to supply one of a plurality of channels of the filtered WDM input signal at a respective one of a plurality of outputs. Each of the plurality of channels corresponds to one of a plurality of wavelengths of the filtered WDM input signal. The optical processor includes a bit-delay interferometer communicating with a respective one of the plurality of outputs of the DEMUX. The optical processor is configured to receive one of the plurality of channels from the DEMUX and output a plurality of demodulated optical signal components.10-01-2009
20090245794Controllable Optical Multiplexer - An inventive controllable optical multiplexer for control of multiplexing channels in a fiber-optic communication system provided with 210-01-2009
20090245793Mapping a Client Signal into Transport Frames - Embodiments of the present invention provide a systems, devices, and methods in which a client signal is divided into a plurality of channels, mapped within transport frames, and combined into a WDM transport signal. These embodiments include intra-nodal redundancy that protects against failure events within the transport transmitter. In particular, redundancy is provided within a network transport transmitter such that redundant paths are available so that electrical channels may be routed around a malfunctioning component within the transmitter.10-01-2009
20090263134DUAL-FILTER OPTICAL NETWORK INTERFACE UNIT AND METHOD OF REMOVING NOISE USING SAME - A network interface unit includes an input for receiving downstream signals from an optical fiber, an optical pathway leading from the input, a laser connected to the optical pathway for transmitting upstream signals in a first wavelength band, and a receiver for receiving downstream signals in a second wavelength band that doesn't overlap with the first wavelength band. A first filter is provided for filtering signals in a third wavelength band from the optical pathway before signals in the third wavelength band reach the receiver, and a second filter is provided between the input and the laser for filtering signals in a fourth wavelength band from the optical pathway, the fourth wavelength band not overlapping with the first wavelength band or the third wavelength band, and an arrangement is also provided for preventing processing of the fourth wavelength band downstream of the second filter. Also a filtering method.10-22-2009
20080232805Wavelength-tunable light source and wavelength-division multiplexed transmission system using the source - The present invention relates to a wavelength-tunable light source whose output wavelength can be externally controlled and a wavelength-division multiplexed transmission system using the source.09-25-2008
20090169211Performance Compensated Tx/Rx Optical Devices - A wavelength division multiplexing system has a wavelength division multiplexer and a wavelength division demultiplexer. The wavelength division demultiplexer is in series with the wavelength division multiplexer to process at least one optical signal to generate at least one processed optical signal. The wavelength division multiplexer and the wavelength division demultiplexer cooperate to introduce substantially zero total chromatic dispersion in the processed optical signal. In one version, the wavelength division multiplexer and the wavelength division demultiplexer introduce opposing functions of chromatic dispersion into the at least one processed optical signal.07-02-2009
20090245797COMMUNICATION SYSTEM AND APPARATUS - A communication system includes a first communication apparatus included in an initial station, the first communication apparatus transmitting a signal to the intermediate station on a later stage, the first communication apparatus receiving a signal sent from the terminal station and passed through the intermediate station, a second communication apparatus included in the intermediate station, the second communication apparatus receiving a signal from a preceding station and transmitting the signal to a later station, the second communication apparatus passing a signal from the later station to the preceding station, and a third communication apparatus included in the terminal station, the third communication apparatus receiving a signal from the intermediate station on a preceding stage, the third communication apparatus transmitting a signal being passed through the intermediate station and being received at the initial station.10-01-2009
20100014865INTEGRATION OF LASER SOURCES AND DETECTORS FOR A PASSIVE OPTICAL NETWORK - Various methods and apparatuses are described in which an array of optical gain mediums capable of lasing are contained in a single integral unit. The array may contain four or more optical gain mediums capable of lasing. Each optical gain medium capable of lasing supplies a separate optical signal containing a band of wavelengths different than the other optical gain mediums capable of lasing in the array to a first multiplexer/demultiplexer. A connection for an output fiber exists to route an optical signal to and from a passive optical network.01-21-2010
20100014863Optical signal switching device - An optical signal switching device comprises a plurality of broadcast couplers (01-21-2010
20090274464METHOD, SYSTEM AND DEVICE FOR SETTING UP WAVELENGTH CONNECTION - A method, a system, and a device for setting up a wavelength connection are disclosed herein. The method includes obtaining a wavelength path from a source network node to a destination network node and wavelength impairment compensation information of the wavelength path; and setting up the wavelength connection from the source network node to the destination network node according to the wavelength path and performing impairment compensation for wavelength signals in an interface of each network node on the wavelength path according to the wavelength impairment compensation information during setting up the wavelength connection. The device disclosed herein includes a path calculation server, a network node device, and a control server. The system disclosed herein is a network communication system. The embodiments of the present disclosure set up an available wavelength connection efficiently, simply and quickly.11-05-2009
20100183307Optical transmitter outputting a plurality of signal light with a preset wavelength span - An optical transmitter that multiplexes a plurality of signal light each having less chirp characteristic by the CML technique is disclosed. The optical transmitter comprises a plurality of optical modules, a plurality of TEC controllers each driving the TEC in the optical module, a de-multiplexer that de-multiplexes the output of respective modules, an etalon filter, and a monitoring unit that monitors the component of the signal light output from respective modules. The TEC controller controls the temperature of the LD in the module such that two emission wavelengths of the LD each corresponding to the ON level and the OFF level is set in both side of one of the critical wavelengths of the etalon filter where the transmittance thereof becomes a maximum.07-22-2010
20100183309System and Method for OCDM-Based Photonic Layer Security Robustness to Archival Attack - A system and method for transporting encrypted data having a transmitter and a receiver is provided. The transmitter generates a sequence of optical pulses, which are copied and output as identical channels. The identical channels are modulated by a plurality of modulators using data to generate a modulated data signal. Respective spectral phase encoders coupled to each of the plurality of data modulators encode respective modulated data signals using a plurality of mutually orthogonal phase codes that are individually associated with the respective spectral phase encoder. These encoded data signals are combined and code-scrambling by a spectral phase scrambler t using a scramble code as an encryption key to generate an encrypted signal. A receiver reverses the encryption to extract the data.07-22-2010
20100189440Methods and Systems for Transmitting Data in Scalable Passive Optical Networks - Systems and methods according to these exemplary embodiments provide for methods and systems that enable decoupling of medium access control (MAC) functions from other optical transceiver functions to, for example, promote scalability of passive optical networks (PONs). A MAC frame processing unit can communicate MAC frames to optical transceiver modules via an interconnect using an encapsulating frame according to another communications protocol, e.g., XAUI.07-29-2010
20090297151Optical transmitting apparatus and optical transmitting and receiving apparatus - An optical transmitting apparatus includes an unused-wavelength determining unit. The unused-wavelength determining unit monitors the wavelength of the optical signal transmitted by transmitting apparatuses to determine an unused wavelength currently not in use. The transmitting apparatuses contain a stopping unit that stops transmitting the optical signal when no signal is input, an unused-wavelength obtaining unit that obtains the unused wavelength determined by the unused-wavelength determining unit after the optical signal transmission is stopped and is then restarted, and a transmitting unit that converts a new signal to an optical signal of the unused wavelength obtained by the unused-wavelength obtaining unit to transmit the optical signal to the receiving apparatus.12-03-2009
20100183308Registration of Device Characteristics with Optical Layer for Use in Establishing Connections Through an Optical Network - Disclosed are, inter alia, methods, apparatus, computer-storage media, mechanisms, and means associated with registration of optical device characteristics of optical network devices with an optical control layer of the optical network for use in establishing compatible connections through the optical network. Especially end network devices and internal network optical devices that regenerate the optical signal register their communication capabilities of their optical interfaces with the optical control layer of an optical network. This registration allows a light path to be established through the optical network which is compatible with the registered capabilities. The optical control layer may be centralized in an optical layer server and/or distributed among optical devices in the optical network, such as on control processors in multiple, optical layer devices.07-22-2010
20100189441METHOD AND DEVICE FOR HITLESS TUNABLE OPTICAL FILTERING - The method for filtering an optical signal comprising a plurality of channels lying on a grid of optical frequencies equally spaced by a given frequency spacing and occupying an optical bandwidth, comprises: a) splitting the optical signal into a first and a second portion spatially separated, wherein the first portion comprises the channels which lie on a first sub-grid comprising a first set of the optical frequencies equally spaced by the double of the frequency spacing and the second portion substantially comprises the remaining channels; b) operating a first optical filter comprising a plurality of resonators, wherein a first resonator of the plurality is optically coupled to the first portion and the remaining resonators are optically coupled in series to the first resonator, so that a respective resonance of each one of the plurality of resonators falls within a first frequency band having bandwidth less than or equal to 15 GHz and comprising a first channel belonging to the first portion; c) operating a second optical filter comprising a plurality of respective resonators, wherein a respective first resonator of the plurality is optically coupled to the second portion and the remaining resonators are coupled in series to the first resonator, so as to obtain a first separation between each resonance of at least one resonator of the second optical filter falling within the optical bandwidth and a respective resonance of at least another different resonator of the second optical filter nearest to said each resonance, the first separation being greater than or equal to 25 GHz; and d) recombining the first and second filtered portions. A corresponding optical device for filtering an optical signal is disclosed.07-29-2010
20080212966Optimised Multiplexer/Demultiplexer Optical Structure - An optical demultiplexing structure and method for demultiplexing channels from a wavelength multiplexed optical signal comprising a first optical filter (09-04-2008
20100239259OFDM Transponder Interface With Variable Bit Transfer Rate in Optical Communications Systems - OFDM (Orthogonal Frequency Division Multiplexing) has been proposed for processing signals over WDM channels in an optical network. The number of OFDM sub-carrier channels utilized in transmitting optical signals from a transmitting node to a remote is adapted to the quality of transmission in a WDM channel. Responsive to control signals from the remote node, the number of used sub-carrier channels is set to optimize optical performance of the WDM channel.09-23-2010
20130216231OPTICAL COMMUNICATION SYSTEM, TRANSMISSION APPARATUS AND RECEPTION APPARATUS, AND TRANSMISSION METHOD AND RECEPTION METHOD - An optical communication system, a transmission apparatus and a reception apparatus, and a transmission method and a reception method are provided. The transmission apparatus transmits an optical signal, and comprises: at least one encoder for encoding at least one data signal, respectively; at least one first modulator for performing first modulation on the at least one encoded data signal, respectively, and generating at least one first modulated signal; at least one second modulator for performing second modulation, which is DFT-spread-OFDM modulation, on the at least one first modulated signal, respectively, and generating at least one second modulated signal; and an up-converter for up-converting the at least one second modulated signal into the optical signal to be transmitted. Thus, a PAPR of the optical OFDM transmission signal is decreased, a signal distortion caused by non-linearity of optical devices is reduced, and a reception quality of the signal is improved.08-22-2013
20090310968MULTIPLE WAVELENGTH LIGHT SOURCE, AND GENERATION METHOD FOR MULTIPLE WAVELENGTH LIGHT - It is an object of the present invention to provide a multiple wavelength light source capable of generating lights of more wavelengths, and a generation method for multiple wavelength light using a multiple wavelength light source.12-17-2009
20100221012BURST MODE RARE EARTH-DOPED FIBER AMPLIFIER - It is an object of the present invention to provide a rare earth doped fiber whose transient response is suppressed and an optical amplifier for optical packet communication having a good characteristic even if there is little traffic.09-02-2010
20100129077TECHNIQUES FOR IMPLEMENTING A DUAL ARRAY WAVEGUIDE FILTER FOR A WAVELENGTH DIVISION MULTIPLEXED PASSIVE OPTICAL NETWORK - Techniques for implementing a dual array waveguide filter for a wavelength division multiplexed passive optical network (WDM-PON) are disclosed. In one particular exemplary embodiment, the techniques may be realized as an apparatus for implementing a dual waveguide filter for a wavelength division multiplexed passive optical network (WDM-PON). The apparatus may include a first light source configured to output a first broadband optical signal for generating a downstream optical signal. The apparatus may also include a second light source configured to output a second broadband optical signal for generating an upstream optical signal. The apparatus may further include a dual array waveguide filter having a first optical transmission path and a second optical transmission path, wherein the first optical transmission path is configured to spectrally slice the first broadband optical signal and the second optical transmission path is configured to demultiplex the upstream optical signal.05-27-2010
20100135663Repeater and repeating method - A repeater is disclosed that transmits an optical signal using wave division multiplexing. The repeater includes a demultiplexing unit that separates plural channels contained in the optical signal, an adjusting unit that adjusts at least optical power of each of the channels according to a control signal, a multiplexing unit that outputs a multiple wavelength signal in which the channels are multiplexed, and a monitoring unit that determines a modulation scheme and a bit rate of the optical signal for each of the channels so as to generate the control signal.06-03-2010
20100196011Wavelength Division and Time Division Multiplex Mixing Passive Optical Network System, Terminal and Signal Transmission Method - A wavelength division and time division hybrid multiplexing passive optical network system, terminals and a signal transmission method are disclosed in the present invention. The system comprises: a plurality of optical modules at the optical line terminal side connecting to an office all-optical wavelength conversion unit, the all-optical wavelength conversion unit connecting with a subscriber all-optical wavelength conversion unit via a fiber, and the subscriber all-optical wavelength conversion unit connecting with a plurality of optical couplers, and each optical couplers connecting with a plurality of optical network units respectively; the present invention facilitates full use of the existing source of access network and ensures a smooth transition from the time division multiplexing passive optical network to the optical access network of the next generation without changing the structure of the current time division passive optical network.08-05-2010
20100021167Wavelength selecting switch - In a wavelength selecting switch, light output from an input port of an input/output optical system is angularly dispersed according to a wavelength thereof, with a spectral element. Then the lights of respective wavelengths are collected by a light collecting optical system and reflected with a corresponding reflecting mirror of a mirror section. The reflected light corresponding to the angle of the reflecting mirror, is input to an output port at an output destination of the input/output optical system. The respective output ports of the input/output optical system each have a lens coupled to an end face of an optical fiber, and the lens has a structure where a focal length of a first region corresponding to inside a variable range of attenuation is different from a focal length of a second region corresponding to outside the variable range. As a result, a change in intensity of output light (coupling efficiency) at the time of an angle change of the reflecting mirror, and cross talk to an adjacent port can be reduced simultaneously.01-28-2010
20090074415PMD INSENSITIVE DIRECT-DETECTION OPTICAL OFDM SYSTEMS USING SELF-POLARIZATION DIVERSITY - A self-polarization diversity technique to combat PMD in a direct-detection optical OFDM system. This technique does not require any dynamic polarization control, and can simultaneous compensate PMD in a WDM system with one device. Simulation results show that this technique virtually completely eliminates the PMD impairments in direct-detection optical OFDM systems.03-19-2009
20090245798OPTICAL CIRCUIT AND RECEIVER CIRCUIT - An optical circuit that converts a phase-modulated optical signal into intensity-modulated signal light in accordance with a phase, the optical circuit including a square mode distribution forming portion that forms a plurality of interfering signals each assuming a square mode shape, the interfering signals having respective phases shifted from each other by a certain angle, a light interference portion that creates a signal having a certain mode distribution, from the interfering signal, and that applies a Fourier transform to the signal having the certain mode distribution, and an output portion that has a plurality of waveguides each provided in correspondence with the phase and that outputs an optical signal that has been output from the light interference portion.10-01-2009
20110026923APPARATUS AND METHOD FOR OLT AND ONU FOR WAVELENGTH AGNOSTIC WAVELENGTH-DIVISION MULTIPLEXED PASSIVE OPTICAL NETWORKS - In a Wavelength-Division-Multiplexed Passive Optical Network (WDM-PON) utilizing a conventional downstream optical signal reusing method, there is an inventory problem that different optical transmitter types need to be provided for the operation, management, replacement, etc. of a system. A WDM-PON system according to the present invention, includes: a seed light (SL) unit generating a seed light whose wavelength intervals and center wavelengths are adjusted using at least one seed light source; an optical line terminal (OLT) receiving the wavelength-multiplexed seed light from the seed light unit, transmitting a downstream optical signal to a subscriber of the WDM-PON, and receiving a upstream optical signal from the subscriber; and an optical network unit (ONU) receiving the downstream optical signal from the OLT, flattening and modulating the downstream optical signal with upstream data so that the downstream optical signal is reused for carrying upstream data. It is possible to improve the quality and reliability of downstream transmission by sufficiently increasing an extinction ratio, and improve the quality and reliability of upstream transmission by sufficiently flattening an input downstream optical signal in a semiconductor optical amplifier.02-03-2011
20090208215METHOD AND DEVICE FOR STABILIZING MULTI-CHANNEL OPTICAL SIGNAL WAVELENGTHS - A method for stabilizing multi-channel optical signal wavelengths includes the following steps. A first detecting signal is stacked on a plurality of driving signals in sequence. A plurality of optical signals generated after being driven by the plurality of driving signals is combined into one optical total signal. A wavelength detection is performed on the optical total signal. A second detecting signal with a frequency band the same as that of the first detecting signal is extracted from the signals obtained after the wavelength detection. The wavelength of the optical signal in the corresponding channel among the multiple channels is controlled according to the second detecting signal. A device for stabilizing multi-channel optical signal wavelengths is also provided. Using the above method or device, the multi-channel optical signal wavelengths can be stabilized, which requires less elements, and has a simple circuit structure, a high integration level, and a low cost.08-20-2009
20100221011Optical Transmission Between a Central Terminal and a Plurality of Client Terminals via an Optical Network - A system and an associated method of bidirectional optical transmission between a central terminal (09-02-2010
20110236022NETWORK MANAGEMENT SYSTEM - A network including nodes configured to provide auto-discovery and those that do not are provided in a network. The nodes that do not provide auto-discovery may be provided as end points or terminating nodes in the network. A path or circuit identifier is entered into a database at those nodes and communicated to a network management system. The network management system compares the path identifiers, and, if the two match, the network management system designates the nodes associated with the path identifiers as terminating nodes. A path through the network connecting these nodes can then be determined and monitored. In addition, fiber connection information may further be stored at each node and communicated to the network management system, such that links along the path can also be identified by the network management system. Thus, path determination and monitoring in a network including non-auto-discovering nodes can thus be obtained.09-29-2011
20090110401Controllable Optical Add/Drop Multiplexer - The inventions relate to a method for operating a controllable selective optical add/drop channel for fiber-optic communication system provided with 204-30-2009
2010032263240, 50 and 100 GB/S OPTICAL TRANSCEIVERS/TRANSPONDERS IN 300PIN AND CFP MSA MODULES - Disclosed by way of exemplary embodiments, a 40/50/10 Gb/s Optical Transceivers/transponders which use opto-electronic components at data rates collectively that are lower than or equal to half the data rate , using two optical duobinary carriers. More specifically, the exemplary embodiments of the disclosed optical transceivers/transponders relate to a 43 Gb/s 300 pin MSA and a 43˜56 Gb/s CFP MSA module, both include a two-carrier optical transceiver and the appropriate hardware architecture and MSA standard interfaces. The two-carrier optical transceiver is composed of a pair of 10 Gb/s optical transmitters, each using band-limited duobinary modulation at 20˜28 Gb/s. The wavelength channel spacing can be as little as 19˜25 GHz. The same principle is applied to a 100 Gb/s CFP module, which is composed of four tunable 10 Gb/s optical transmitters, with the channel spacing between optical carriers up to a few nanometers.12-23-2010
20110008048Optical system using optical signal and solid state drive module using the optical signal - An optical system and an SSD module that maintain optimal SI, PI and EMI characteristics without a shield based on a ground voltage and an impedance match. The optical system includes a solid state drive (SSD) module and an input/output (I/O) interface. The SSD module includes a plurality of solid state memory units. The input/output (I/O) interface receives data to be written to at least one of the solid state memory units from a main memory unit, the input/output (I/O) interface transmits data written in at least one of the solid state memory units to the main memory unit. The SSD module and the I/O interface transmit and receive data using an optical medium.01-13-2011
20090067842OPTICAL PULSE REGENERATION BASED ON PULSE TEMPORAL SHAPING - An optical pulse regeneration unit comprising means for broadening the temporal width and flattening the center portion of an optical pulse and slicing means for slicing the pulse at a point in time so that in use, the pulse immediately after the slicing means contains only the portions of the pulse which at the slicing means were within a specific temporal width/interval about the point in time.03-12-2009
20090067843Optical Wavelength-Division-Multiplexed (WDM) Comb Generator Using a Single Laser - Apparatus, systems and techniques that use a single laser to generate desired optical WDM comb frequencies.03-12-2009
20090034976Maintaining Correlated Virtual Data Streams Through a Network - Embodiments of the invention are described in which correlated virtual data streams are managed within an optical network connection. In certain embodiments of the invention, a client signal is allocated across a plurality of transport wavelength channels according to various transposition methods. The assignment of portions of the client signal to corresponding wavelengths may depend on various factors including channel utilization within the transport network and skew characteristics between particular wavelengths.02-05-2009
20090034975Methods and apparatuses for handling multiple failures in an optical network - Methods and apparatuses for handling multiple failures in an optical network are described herein. In one embodiment, an exemplary method includes receiving a demand for allocating a protection path that meets a set of disjointness constraints with respect to a working path, the protection path suitable to be shared with one or more other working paths, each of the working paths associated with a priority for obtaining the shared protection path, and in response to the demand, selecting a protection path that meets the set of disjointness constraints with respect to the working path and has not been shared with another working path having the same priority as the working path associated with the protection path in demand. Other methods and apparatuses are also described.02-05-2009
20110033186Method, System and Radio Station for Interference Cancellation - A method detects a first baseband signal sent by a first sending station via an air interface to a first radio station of a radio communications system. A first receive signal, which contains the first baseband signal superposed with at least a second baseband signal sent by a second sending station to a second radio station, is received by the first radio station. The first radio station uses at least a second receive signal received by the second radio station for detection of the first baseband signal. The second receive signal contains at least the second baseband signal, and is used to at least partially cancel the interference in the first receive signal caused by the second baseband signal.02-10-2011
20110033187SPLIT/SMART CHANNEL ALLOCATED WDM-PON ARCHITECTURE - Various example embodiments are disclosed. According to an example embodiment, a dual split passive optical network (PON) may be provided that includes an optical splitting device, and a first and second distribution fibers connected to the optical splitting device. A first cyclic AWG may be coupled to the optical splitting device via the first distribution fiber and a second cyclic AWG may be coupled to the optical splitting device via the second distribution fiber. In other example embodiments, an asymmetric power splitting ratio may be used for the splitting device, or optical seeds and/or optical data signals may be allocated to each of the cyclic AWGs based on a performance of the optical data signals and/or power loss/attenuation of the respective distribution fibers.02-10-2011
20110033188PLUGGABLE CONVERSION MODULE FOR A DATA TRANSPORT CARD OF A WAVELENGTH DIVISION MULTIPLEXING SYSTEM - A data transport card comprising an interface to receive high speed data streams from at least one client, and a pluggable conversion module which converts said data streams into optical data signals and couples these optical data signals into at least one wavelength division multiplexing channel for transport of said optical data signals via an optical fibre.02-10-2011
20090214214Optical Fiber Transmission System with Noise Loading - A system and method for loading unutilized channels of a WDM system with noise to improve system performance. A transmitter amplifier may impart noise to unutilized channels by reducing amplifier input or providing feedback of the amplifier output. Noise signals may also be looped back to the transmitter from received signals.08-27-2009
20090214213MODULATION DEVICE FOR GENERATING OPTICAL SIGNAL WITH QUADRUPLE FREQUENCY AND METHOD THEREOF - The present invention discloses a modulation device for generating an optical signal with quadruple frequency and the modulation method thereof. The modulation device in the present invention utilizes a commercial integrated modulator, a RF signal generator and a phase shifter to generate an optical signal with quadruple frequency. When the RF signal generator generates a first modulation signal, and the phase shifter shifts the first modulation signal by 90 degrees to generate a second modulation signal, the integrated modulator is biased to transmit the optical signal in maximum value and to modulate the first and second modulation signal so as to generate a output optical signal with quadruple frequency.08-27-2009
20090214212METHOD AND DEVICE FOR CHANNEL-ADAPTED SIGNAL TRANSMISSION IN OPTICAL NETWORKS - A method for optical data transmission in a wavelength multiplexing system having at least two transmission channels of different wavelengths includes determining at least one value which is a measure of a physical property of an optical data transmission path of the wavelength multiplexing system; and automatically adjusting a transmission parameter of at least one of the transmission channels as a function of the determined at least one value.08-27-2009
20110044691APPARATUS AND METHOD FOR DETECTING OPTICAL SIGNALS - Disclosed are an apparatus and method for detecting optical signals. The optical signal detection apparatus includes: a signal receiver to convert a received optical signal into an electrical signal; a threshold decision unit to establish a mathematical model based on the electrical signal and to decide an optimized threshold value based on the mathematical model; and a signal detector to detect the electrical signal based on the optimized threshold value. Hence, since threshold values optimized adaptively according to received signals are used, a bit error rate may be lowered and accordingly detection performance may be improved.02-24-2011
20110116799Tunable Coherent Optical Time Division Reflectometry - An apparatus comprising an optical transmitter, a coarse tuner coupled to the optical transmitter and having a first tuning range, a fine tuner coupled to the optical transmitter and having a second tuning range smaller than and within the first tuning range, a wavelength division demultiplexer coupled to the optical transmitter and to a plurality of optical fibers, and a detector coupled to the optical transmitter and the wavelength division demultiplexer. A network component comprising at least one processor configured to implement a method comprising detecting an Optical Time Domain Reflectometry (OTDR) signal spectrum that has a modulated pattern, and detecting a reflected OTDR signal spectrum that has a shifted modulated pattern comprising a frequency shift with respect to the OTDR signal spectrum and a time shift proportional to the frequency shift.05-19-2011
20100014864COLORLESS OPTICAL TRANSCEIVER AND OPTICAL COMMUNICATION SYSTEM - A colorless optical transceiver and an optical communication system including the same are disclosed herein. A controlling unit of the colorless optical transceiver forms a control current based on intensity of an external-injection light provided from an external light source. A light source driving unit coupled to the controlling unit forms a driving current based on the control current. An internal light source is coupled to the light source driving unit, the internal light source being configured to receive the external-injection light and the driving current and to convert the driving current into a colorless sending light, wherein a wavelength of the colorless sending light is locked by that of the external-injection light. The light output from the internal light source is controlled based on intensity of external-injection light calculated by using optical loss, which varies according to the distances between optical devices and connection state. Thus, the light output from the colorless optical transceiver and the extinction ratio may be stabilized.01-21-2010
20100003032Integration of WDM channels with disparate bit rates - Systems and methods for upgrading selected wavelengths in a WDM link to higher data rates at minimal expense are provided. Error correction coding techniques are employed such that the data encoded onto the upgraded wavelengths experiences higher coding gain than that experienced by data encoded on the non-upgraded wavelengths. This increases receiver sensitivity without the use of expensive opto-electronic components. In one embodiment, Reed-Solomon coding is employed on the upgraded wavelengths and no error correction coding is employed on the remaining wavelengths. These techniques may also be applied to new WDM links carrying channels with disparate bit rates.01-07-2010
20100054741WAVELENGTH ROUTING SYSTEM - A wavelength routing system includes a plurality of nodes (03-04-2010
20100054742MULTI-CORE HOLEY FIBER AND OPTICAL TRANSMISSION SYSTEM - A multi-core holey fiber with suppression of crosstalk deterioration among transmitted optical signals in a plurality of cores, and an optical transmission system using the fiber are disclosed. The multi-core holey fiber comprises a plurality of cores arranged separately from each other, and a cladding surrounding the plurality of cores wherein the cladding has plurality of holes arranged in a triangular lattice shape to create hole layers around the plurality of cores. Additionally, d/Λ is not more than 0.5, where Λ [μm] is lattice constant of the triangular lattice, d [μm] is diameter of each of the holes; a distance between adjacent cores is equivalent to not less than six hole layers; the cores arranged farthest from the center of the multi-core holey fiber is surrounded by not less three hole layers; and the sum of the coupling coefficients between the adjacent cores is not more than 1.6×1003-04-2010
20110176809OPTICAL TRANSMISSION SYSTEM AND OPTICAL TRANSMISSION METHOD - After implementing a scrambler upon an electric signal of digital signals to be transmitted to a user terminal, this electric signal is converted into a digital optical signal, and an analog optical signal and this digital optical signal are multiplexed by wavelength division multiplexing, thereby reducing influence of cross-talk interference that is exerted on the analog optical signal by the digital optical signal.07-21-2011
20110081151Generation and Coherent Detection of High-Speed Orthogonal DWDM Optical Signal - A high speed orthogonal dense wavelength division multiplexing DWDM signal generator includes a multi-peak continuous wave signal generator responsive to a light source, an optical filter for separating multi-peaks of lightwaves from the generator; and a polarization multiplexing stage responsive to the multi-peaks of lightwaves from the optical filter for providing a polarization multiplexing optical signal. The generator includes a cascaded phase modulator and intensity modulator driven by a repetitive frequency (I) to generate multiple spectral peaks, each peak being modulated by an optical modulator driven by a respective baud rate (f baud/s) electrical signal.04-07-2011
20110249973OPTO-ELECTRONIC SIGNAL PROCESSING METHODS, SYSTEMS, AND APPARATUS FOR OPTICAL SENSOR INTERROGATION - Opto-electronic signal processing systems, apparatus and methods to extract a measured parameter from one or more interrogated optical sensors are disclosed. The apparatus includes an integrated laser module, an electronic control and processing unit, an optical coupling element, and one or more light receivers. Light is reflected back from the optical sensor through the optical coupling element to the light receiver(s). The electronic control and processing unit controls the wavelength of the integrated laser module using thermal control and, at the same time, detecting the wavelength of the integrated laser module using a wavelength selective element of the integrated laser module. According to the method, a wavelength sweep from the integrated laser module wavelength is swept, simultaneously measured and stored in memory of the electronic control and processing unit. The optical sensor response is recorded during the sweep and combined with stored emitted wavelengths to obtain spectral characteristics of interrogated optical sensor. Numerous other aspects are provided.10-13-2011
20110069959OPTICAL INTERLEAVER AND DEINTERLEAVER - Optical interleavers and deinterleavers. In one example embodiment, an optical deinterleaver includes first, second, and third filter cells interleaved with first and second waveplates. The filter cells are configured to filter optical signals propagating on first, second, and third paths of an optical loop. The optical deinterleaver also includes a retro reflector optically coupled with the filter cells and waveplates. The retro reflector is configured to reflect the optical signals between the first path and the second and third paths to form the optical loop. The optical deinterleaver further includes first, second, and third single-fiber collimators optically coupled to the first, second, and third paths of the optical loop, respectively.03-24-2011
20090022495DEPLOYMENT OF ELECTRO-OPTIC AMPLITUDE VARYING ELEMENTS (AVEs) AND ELECTRO-OPTIC MULTI-FUNCTIONAL ELEMENTS (MFEs) IN PHOTONIC INTEGRATED CIRCUITS (PICs) - Electro-optic amplitude varying elements (AVEs) or electro-optic multi-function elements (MFEs) are integrated into signal channels of photonic integrated circuits (PICs) or at the output of such PICs to provide for various optical controlling and monitoring functions. In one case, such PIC signal channels may minimally include a laser source and a modulator (TxPIC) and in another case, may minimally include a photodetector to which channels, in either case, an AVE or an MFE may be added.01-22-2009
20110150481ELECTRICAL RETURN-TO-ZERO (ERZ) DRIVER CIRCUIT - Consistent with the present disclosure, clock-and-data recovery (CDR) circuitry and driver circuitry are provided on a chip that is separate from the driver circuitry, thereby reducing the amount of power consumed by the driver circuitry and simplifying system design. In one example, timing of the ERZ signals is controlled by a feedback loop that adjusts the phase of a data carrying signal relative to a clock signal, such that the phase has a desired value. Timing of the ERZ signals may thus be adjusted to minimize errors.06-23-2011
20090324229OPTICAL TRANSMISSION APPARATUS AND CONTROL METHOD THEREFOR - An optical transmission apparatus comprising a first detector for detecting the power of the supervisory signal light separated from received wavelength-division multiplexed signal lights; a second detector for detecting the power of the wavelength-division multiplexed signal lights after the separation of the supervisory signal light; a gain-controlled type optical amplifier for amplifying the wavelength-division multiplexed signal lights; an optical attenuator coupled to the amplifier; and a control unit for controlling the optical amplifier and the optical attenuator so as to keep the output level of the wavelength-division multiplexed signal lights to a predetermined target value, wherein the control unit restrains automatic output level control by the optical attenuator when the supervisory signal light power fluctuates within its permissible range and fluctuations in the signal light power have deviated from its permissible range.12-31-2009
20090324230OPTICAL TRANSMISSION SYSTEM USING FOUR-WAVE MIXING - Provided is an optical transmission system using four-wave mixing which is configured in a WDM-PON topology where a signal light between an optical line terminal 12-31-2009
20090324227Multi-Channel Optical Transport Network Training Signal - Systems and methods are provided for multi-channel ITU G.709 optical transport network (OTN) communications The transmission method accepts an ITU G.709 OTN frame including an OTU overhead (OH) section and an ODU section. A forward error correction (FEC) parity section with a training signal is appended to the ITU G.709 OTN frame, to create a training-enhanced (TE) OTN frame. All, or a portion of the TE OTN may be buffered in a tangible memory medium in preparation for striping. The training-enhanced OTN frame is then striped into n parallel streams, and n TE_OTN-PFs (Parallel Frames) are supplied.12-31-2009
20110211839LOW-COST WDM SOURCE WITH AN INCOHERENT LIGHT INJECTED FABRY-PEROT LASER DIODE - The present invention discloses a low-cost light source for optical transmission systems and optical networks based on wavelength-division multiplexing (WDM) technology. A light source in accordance with the present invention is implemented by externally injecting a narrow-band incoherent light into a Fabry-Perot laser diode (F-P LD). After injection of narrow-band incoherent light, the output of F-P LD becomes wavelength-selective rather than multi-mode and the output wavelength of F-P LD coincide with the peak wavelength of the injected incoherent light.09-01-2011
20110255871Mode-Locked Optical Amplifier as a Source for a wdm-WDM Hierarchy Architecture - The present invention relates to advances in the field of reconfigurable optical networks. In particular, the present invention provides improvements in the technology of light sources for use in optical networks. The optical network according to the present invention includes a single light source that can be used to emit all of the bands and channels needed for transmission. In particular, the single light source in the optical network of the present invention is a mode-locked laser.10-20-2011
20110164878METHOD AND SYSTEM FOR IMPLEMENTING A WIRELESS NETWORK - Aspects of the present invention provide a multi-band hybrid Gigabit wireless communication system which is enabled by a number of different complementary access technologies to realize ubiquitous hyper-connectivity, true broadband, seamless operation and low power consumption. The system is capable of serving fixed, nomadic and mobile scenarios. The multi-band wireless system is a low power wireless system which operates in different frequency bands covering the spectrum from radio wave to optical wave by making use of both regulated bandwidths and unregulated bandwidths. Using low power distributed antenna and low power indoor and outdoor antennas enables the use of unregulated bandwidths as well as regulated bandwidths as the low power nature of the signals reduces the possibility of interference with the regulated use of the signals.07-07-2011
20110020003Generating A 400-Gbit/s Single-Channel Optical Signal - A method for generating a 400 Gb/s single channel optical signal from multiple modulated subchannels includes carving respective modulated subchannels into return-to-zero RZ modulated subchannels having non-overlapping peaks with intensity modulators having a duty cycle less than 50%, and combining the subchannels into a single channel signal aggregating the bit rate of each of the subchannels. The subchannels are combined with a flat top optical component for increased subsequent receiver sensitivity.01-27-2011
20110020004DATA TRANSMISSION METHOD, DATA PROCESSING NODE, AND DATA TRANSMISSION SYSTEM - A data transmission method, a data transmission system and a data processing node are provided to improve the resource utilization. The data transmission method includes the following steps: a second data processing node receives control information sent from a first data processing node through a preset control channel, where the control information includes at least bandwidth information of a data channel for sending optical burst data and corresponds to the service information of optical burst data of the first data processing node; the second data processing node controls the transmission of pending optical burst data according to the bandwidth information. A data processing node and a data transmission system are also provided.01-27-2011
20110026924OFDM OPTICAL TRANSMITTER AND OPTICAL TRANSMISSION METHOD - An OFDM optical transmitter and optical transmission method is provided. The OFDM optical transmitter includes a signal converter controlling amplitude of each of data signals according to a position of each of the data signals and converting the controlled data signal into a time-domain signal. Accordingly, it is possible to generate optical OFDM carriers which are uniform in size.02-03-2011
20110026926TERMINAL DEVICE, METHOD OF CONTROLLING THE SAME, COMPUTER-READABLE STORAGE MEDIUM STORING PROGRAM THERFOR02-03-2011
20110026925Hybrid Optical Add-Drop Multiplexing Network and Wavelength Allocation for the Same - An optical add-drop network and wavelength allocation for the same wherein the system bandwidth is separated into a dedicated channel band and re-used channel bands, separated by guard bands, to allocate terminal connections to achieve a minimum number of re-used channel bands for the desired terminal connectivities.02-03-2011
20100178057SIGNAL METHOD AND APPARATUS - Methods and apparatus for generating and processing a signal are disclosed. The signal may comprise a plurality of mutually orthogonal subcarriers constituting a plurality of bands. The signal may be either an optical or a radio frequency signal.07-15-2010
20110110665ANTI-REFLECTION COATED QUANTUM DOT RESONATOR FOR WAVELENGTH DIVISION MULTIPLEXING OPTICAL COMMUNICATION - An AR coated quantum dot resonator implementing a wavelength independent light source to resolve a drawback of degradation in the property of a high temperature optical output due to AR coating of LED or wavelength locked light source, which is filtered to a narrow line width, is disclosed. In one embodiment, a gain medium includes at least one quantum dot and an anti-reflection (AR) coated reflection plane at one of front and rear planes of the gain medium. The gain medium has a wide line width due to different sizes and distribution of a plurality of quantum dots. The line width includes entire wavelength channels of a WDM or WDM-PON. Also, the AR coated reflection plane is a front reflection plane having a lower reflectivity (e.g., 0.001% to 1%.) than that of a rear reflection plane.05-12-2011
20100329679TUNABLE OPTICAL DEMULTIPLEXER - A tunable optical demultiplexer includes a control circuit and one or more heaters thermally coupled to waveguides of an optical demux. The control circuit is in signal communication with the one or more heaters and includes a processor coupled to a memory. The control circuit is configured to receive an optical channel group (OCG) identification signal and adjust the power delivered to the heaters in response to the OCG identification signal and based on parameter values stored in the memory. The optical demux outputs a plurality of optical signals at a corresponding one of a plurality of outputs. The transmission characteristics of the optical demux are varied depending on the amount of power delivered to the heaters. The varying of the transmission characteristics of the optical demux adjusts the spectral shifting of the plurality of wavelengths output by the optical demux.12-30-2010
20100329682REMODULATING CHANNEL SELECTORS FOR WDM OPTICAL COMMUNICATION SYSTEMS - The present invention provides a remodulating channel selector for a wavelength division multiplexed optical communication system. The remodulating selector receives a WDM input signal, selects a particular optical channel from the WDM signal and places the information from the selected signal onto a newly-generated optical output signal. The wavelength of the output optical signal can be the same as or different from one of the optical channels which comprises the WDM input signal. When used in a WDM optical communication system with remodulators at the transmission input, the remodulating selectors provide complete control over the interfaces with optical transmitters and receivers, permitting use with a broad range of optical equipment.12-30-2010
20100329680OPTICAL NETWORKS - The invention relates to improvements in or relating to optical networks. Methods and apparatus are disclosed for providing communications services to at least one user. Transmission of an optical signal in the downstream direction is described comprising at least one Wavelength Division Multiplexing channel such that at least one of the channels is an unmodulated channel. The unmodulated channel is arranged to transmit user data from the at least one user in the upstream direction.12-30-2010
20100329678Micro Free-Space WDM Device - Techniques for designing optical devices that can be manufactured in volume are disclosed. In an exemplary an optical assembly, to ensure that all collimators are on one side to facilitate efficient packaging, all collimators are positioned on both sides of a substrate. Thus one or more beam folding components are used to fold a light beam up and down through the collimators on top of the substrate and bottom of the substrate.12-30-2010
20110135309WAVELENGTH DIVISION MULTIPLEXING-PASSIVE OPTICAL NETWORK (WDM-PON) - Provided is an Optical Line Terminal (OLT). The OLT may include a first Wavelength division multiplexer/demultiplexer (WDM MUX/DeMUX) to perform a wavelength demultiplexing on seed light received from a seed light source, and a second Wavelength division demultiplexer (WDM DeMUX) to receive, from at least one ONU/ONT, an upstream optical signal generated using the seed light having the wavelength demultiplexing performed, and to perform a wavelength multiplexing on the received upstream optical signal.06-09-2011
20110135308DISTRIBUTED ANTENNA SYSTEM FOR MIMO SIGNALS - A distributed antenna system (DAS) includes a multiple-input and multiple-output (“MIMO”) base station configured to output at least a first and second signal, and a hybrid coupler coupled thereto, the coupler configured to receive the first and second signal from the MIMO base station on respective first and second ports and provide an output signal on at least one output port, the output signal including at least a portion of the first signal and at least a portion of the second signal. The DAS further includes a master unit communicating with the coupler and configured to receive at least the output signal, and at least one remote unit communicating with the master unit and configured to communicate the output signal to a device.06-09-2011
20110052197Compression of generated optical continuum utilizing higher-order-mode fiber - An arrangement for providing pulse compression at the output of an optical continuum source (advantageously used in spectral slicing applications) includes a section of higher-order mode (HOM) fiber configured to exhibit a predetermined dispersion in at least a portion of the predetermined wavelength range and an effective area greater than 40 μm03-03-2011
20110052196Narrow-band DPSK apparatus, system, method - System, apparatus and methods are provided for optical communication which tolerates the tight filtering effects from concatenation of reconfigurable optical add drop multiplexers (ROADMs). An exemplary system includes a receiver configured to receive a Narrow-Band Differential-Phase-Shift-Keyed (NB-DPSK) optical signal. The receiver includes a Delay Line Interferometer (DLI) with a path length difference of less than approximately one bit period and a detector for detecting DLI output to form an electrical signal. The bandwidth of the NB-DPSK optical signal is less than approximately one-half of a first bit rate of a transmitter from which the NB-DPSK optical signal is received. The electrical signal is processed to decode transmitted data. A corresponding transmitter amplifies a first input signal having a first bit rate; and drives a DPSK modulator after amplification to generate the NB-DPSK optical signal, which has a bandwidth less than approximately one-half of the first bit rate.03-03-2011
20110052195OPTICAL DATA COMMUNICATION USING OPTICAL DATA PATTERNS - An optical data system and method for optically transmitting data. The system includes an optical transmitter. The optical transmitter includes a pattern mapper, a light source, and a light limiting device. The pattern mapper maps a data string to a pattern of light pulses. The pattern of light pulses corresponds to a two-dimensional array that is representative of the data string. The light source emits light toward a plurality of optical cables. The light limiting device is coupled to the pattern mapper and interposed between the light source and the optical cables. The light limiting device includes a plurality of light switches to selectively transmit the pattern of light pulses into the optical cables to form the light packet.03-03-2011
20100215371POLARIZATION MODE DISPERSION (PMD) COMPENSATION IN POLARIZATION MULTIPLEXED CODED ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING (OFDM) SYSTEMS - A receiver and method are provided. The receiver includes a detector configured to receive polarization multiplexed coded orthogonal frequency division multiplexing input sequences and generate estimates of unknown transmitted symbols in the input sequences for x- and y-polarization channels with respect to laser phase noise and PMD. A demapper coupled to the detector is configured to partially cancel polarization mode dispersion (PMD) in the input sequences by computing symbol probabilities for the estimates with respect to the laser phase noise, and averaging the symbol probabilities with respect to the laser phase noise. One or more low-density parity-check (LDPC) decoders coupled to the demapper are configured to receive bit probabilities derived from the averaged symbol probabilities and output code words based at least on the bit probabilities. The one or more LDPC decoders iteratively provide extrinsic soft information feedback to the demapper to compensate for the PMD.08-26-2010
20100215372SURFACE PLASMON POLARITON DIRECTION CHANGE DEVICE, READ/WRITE HEAD, LASER-ASSISTED MAGNETIC RECORDING APPARATUS, AND OPTICAL CIRCUIT - This invention provides a surface plasmon polariton direction change device (08-26-2010
20100166425OPTICAL RECEIVER - An optical receiver for receiving a wavelength channel signal light separated out of a wavelength division multiplexed signal light including a plurality of wavelength channel signal lights, the optical receiver includes an optical amplifier for amplifying the wavelength channel signal light, a cyclic filter having a transmission wavelength characteristic of periodically changing transmittance property for a wavelength interval between a wavelength of an adjacent wavelength channel signal light and a wavelength of the wavelength diversion multiplexed signal light, the cyclic filter passing the wavelength channel signal light amplified by the optical amplifier, and a demodulator operably connected to the cyclic filter for demodulating the wavelength channel signal light output from the cyclic filter into an electrical signal.07-01-2010
20100158529METHOD FOR WAVELENGTH ASSIGNMENT IN A WDM NETWORK - In accordance with the present disclosure, a method of configuring a wavelength division multiplexed (WDM) network is presented. The WDM network includes circuits that carry optical signals, with each signal corresponding to a wavelength. The WDM network includes nodes, with links connecting the nodes to one another. Each circuit includes at least one link and at least one node. The method comprises assigning each of the circuits to an optical signal, based on first and second criteria, and configuring the nodes based on the assignment.06-24-2010
20100158531CHANNEL ASSIGNMENT METHOD AND APPARATUS FOR WAVELENGTH-DIVISION-MULTIPLEXED TRANSMISSION SYSTEM - Provided is a channel assignment method in a wavelength-division-multiplexed transmission system. The channel assignment method includes obtaining information about signal modulation schemes from a plurality of optical transmitters, and assigning channels to the respective optical transmitters in consideration of the obtained information about the signal modulation schemes. Accordingly, in transmission of channels of different modulation formats, cross phase modulation is minimized, thereby reducing inter-channel interference.06-24-2010
20100158528System for routing and wavelength assignment in wavelength division multiplexing optical networks - A method for routing and wavelength assignment (RWA) in an optical network with improved heuristics for reducing the computational times required for the RWA. The method minimizes the number of wavelengths by packing the lightpaths using a minimum number of bins in a bin packing problem. Computational efficiency is enhanced by using several novel methods to determine shortest paths and eliminate arcs in a graph that represents the network topology.06-24-2010
20110188859WDM-PON ARCHITECTURE BASED ON EXTERNALLY SEEDED OPTICAL SOURCE - A wavelength-division-multiplexed passive optical network (WDM PON) comprising: a remote node (RN) comprising a light source for generating a seeding signal; and one or more optical network units (ONUs), each ONU comprising a laser source configured for receiving a portion of the seeding light signal from the RN.08-04-2011
20110262140MULTI-WAVELENGTH LIGHT AMPLIFIER - A multi-wavelength light amplifier includes a first-stage light amplifier which has a first light amplifying optical fiber amplifying a light input, a second stage light amplifier which has a second light amplifying optical fiber amplifying a first light output from the first-stage light amplifier, and an optical system which maintains a second light output of the second-stage light amplifier at a constant power level. The first-stage and second-stage light amplifiers have different gain vs wavelength characteristics so that the multi-wavelength light amplifier has no wavelength-dependence of a gain thereof.10-27-2011
20100040373OPTICAL TRANSMISSION DEVICE - In a wavelength-division multiplexing communications system including a plurality of optical transmission devices having an optical amplifier, downstream optical transmission devices transmit gain wavelength characteristic information of an optical amplifier in each of the downstream optical transmission devices to an upstream optical transmission device. The upstream optical transmission device controls gain wavelength characteristics on the basis of the received gain wavelength characteristic information.02-18-2010
20100028006Channel Wavelength Assignment With Transient Reduction - In an automatically switched optical network operating according to a wavelength plan, the wavelengths are assigned to an optical path based on availability, performance and SRS wavelength coupling reduction. First, the wavelengths are grouped in static bins based on their reach versus cost performance, and each bin assumes a ΔQ of a middle wavelength. Then, the bins are moved into subsets of dynamic bins, constructed using bin constraints that account for the particulars of the respective optical path. The path is characterized taking into account the wavelength currently accessing at the end nodes, and the wavelength tandeming through the end nodes. Wavelength selection starts with the bins that satisfy the maximum number of constraints, and the wavelengths are checked sequentially against wavelength constraints; relaxed constraints are also applied when it is not possible to exactly satisfy one or more constraints.02-04-2010
20100028005BULK MODULATION OF MULTIPLE WAVELENGTHS FOR GENERATION OF CATV OPTICAL COMB - A system for generating an optical CATV comb comprising a plurality of wavelength division multiplexed (WDM) optical CATV signals. A set of one or more lasers generate a plurality of narrow-band continuous wave (CW) lights, each CW light having a respective predetermined wavelength and optical power level. An optical MUX couples the plurality of CW lights into a WDM continuous wave light. A broadband optical modulator responsive to a CATV signal modulates the WDM continuous wave light to generate the optical CATV comb.02-04-2010
20100028004OPTICAL COMMUNICATION DEVICE, OPTICAL COMMUNICATION SYSTEM, OPTICAL OUTPUT CONTROL METHOD AND PROGRAM - An input of a command to stop optical output or a command to reduce optical output by a main signal transmitting section is received from the outside. When the input of the optical output stop command or optical output reduction command is received, an inter-device control signal communication section transmits the optical output stop command or optical output reduction command. Based on the input optical output stop command or optical output reduction command, an output of optical signals from the main signal transmitting section is stopped, or else the output level is reduced to less than the output level during normal operation.02-04-2010
20100028003WDM optical transmission system and controlling method thereof - In the WDM optical transmission system, when performing a correction of a control target value of the total light intensity per one channel of the WDM light in each node on a transmission path, a correction value calculation section of each node determines the type of its own node, and if it corresponds to a node (for example, OADM node) that demultiplexes the WDM light into individual channels and performs a predetermined processing, performs correction of the control target value of the total light intensity according to a calculation expression with use of a noise cut ratio. The noise cut ratio is defined according to a filtering characteristic for when demultiplexing the WDM light into individual channels, so that the influence due to removal of the noise components distributed across the intermediate region of each channel due to filtering is reflected in the correction processing of the control target value of the total light intensity.02-04-2010
20100028001Generation Of At Least 100 Gbit/s Optical Transmission - A method includes generating at least two lightwave carriers from a lightwave source, the carriers having a wavelength spacing, creating an up-subchannel and a down-subchannel orthogonal to one another and spaced apart based on the fixed wavelength spacing from modulations of the lightwave carriers according to respective up-converted OFDM signals that are carrier suppressed, and combining one lightwave from the up-subchannel and one lightwave from the down-subchannel into an optical channel for transmission over an optical fiber.02-04-2010
20100028000MODULE WITH BOTH ANALOG AND DIGITAL RECEIVING-TRANSMITTING - A module with both analog and digital receiving-transmitting is provided, which has an optical signal transceiving terminal, an optical signal receiving terminal, a wavelength division unit, a first optical-to-electrical transceiver unit, and a second optical-to-electrical output unit. The first optical-to-electrical transceiver unit is connected to the optical signal transceiving terminal for optical-to-electrical process of computer data communication. The second optical-to-electrical output unit is connected to the optical signal receiving terminal for optical-to-electrical process of analog image signals.02-04-2010
20100027999WAVE DIVISION MULTIPLEXING REPLACEMENT OF SERIALIZATION - A WDM system is used to transfer bytes of data between keyboard, display and camera portions of a hand held device. The data signals are converted into light wavelengths via lasers or LEDs of differing wavelengths and transported over an optical fiber cable. Mems devices help direct the wavelengths to the optical cable and mems devices may be used at the receiving end. The receiver illustratively has a photodiode array to receive the different wavelengths and produce electronic signals. Optical filters and micro-ring resonators may be employed.02-04-2010
20090245800OPTICAL MODULE IMPLEMENTED WITH TRI-PLEXER OPTICAL SUBASSEMBLY - An optical module that implements with a tri-plexer assembly is disclosed. The tri-plexer module comprises a bi-directional module for transmitting digital input and output signals and an analogue optical assembly for receiving analog optical signals. The bi-directional module installs both a light-emitting device and a light-receiving device in a signal package. The analogue optical assembly is assembled such that the optical axis thereof makes a substantially right angle with the optical axis of the bi-directional module. The signal ground of the module is common to the analogue module and to a section for receiving the digital data; while, the chassis ground or the frame ground in the module is isolated from the signal ground.10-01-2009
20100021166Spectrally Efficient Parallel Optical WDM Channels for Long-Haul MAN and WAN Optical Networks - Techniques, apparatus and systems for optical WDM communications that use spectrally efficient parallel optical WDM channels for WAN and MAN networks.01-28-2010
20110217045CROSSTALK MITIGATION IN OPTICAL TRANSCEIVERS - The invention relates to a method of improving the performance of optical receivers within optical transceivers by compensating for crosstalk, both optical and electrical. Optical crosstalk may arise within the optical receiver from a variety of sources including directly from the optical emitter within, indirectly from the optical emitter via losses, and losses of other received wavelengths within the optical transceiver coupled to the optical receiver. Electrical crosstalk may arise for example between the electrical transmission lines of the optical transmitter and optical receiver. The method comprises providing a secondary optical receiver in predetermined location to the primary optical receiver, the optical receivers being electrically coupled such that the crosstalk induced photocurrent in the secondary optical receiver is subtracted from the photocurrent within the primary optical receiver. The method may be applicable to either monolithic and hybrid optical transceivers.09-08-2011
20110085803ROADM TRANSPONDER AGGREGATOR SYSTEMS AND METHODS OF OPERATION - ROADM node systems and methods of operation are disclosed. ROADM node systems may include transponder aggregators including transponders to add signals for switching through the ROADM node. The transponder aggregators may be constrained from adding signals on adjacent channels for simultaneous use. Further, the transponder aggregators may include an optical coupler in lieu of an optical multiplexer. The ROADM system may include a set of wavelength selective switches associated with output ports that can provide an additional filtering function for the added signals prior to transmission on a WDM network.04-14-2011
20090092393Coherent Optical Orthogonal Frequency Division Multiplexing (OFDM) Reception Using Self Optical Carrier Extraction - A method includes producing interference between a received optical OFDM signal and an optical carrier extracted from the received optical OFDM signal to provide optical coherent detection of the received optical OFDM signal. Preferably, producing the interference includes optically splitting the received optical OFDM signal into a first part that is filtered to extract the carrier from the received optical OFDM signal and a second part similar to the received optical OFDM signal.04-09-2009
20120308236APPARATUS FOR INTERFACING BETWEEN DUAL-CARRIER OPTICAL TRANSCEIVER AND WDM OPTICAL TRANSMISSION LINE - The present invention provides an interface apparatus between a dual-carrier optical transceiver and a WDM (wavelength division multiplexing) optical transmission line, including: an optical multiplexer configured to receive a first optical signal modulated by a first optical carrier and a second optical signal modulated by a second optical carrier from the dual-carrier optical transceiver, and multiplex the first optical signal and the second optical signal to output the signals to the optical transmission line; and an optical demultiplexer configured to receive the multiplexed optical signal from the optical transmission line and demultiplex the multiplexed optical signal to output the signals to the dual-carrier optical transceiver.12-06-2012
20100021168GROOMING METHOD AND APPARATUS FOR OPTICAL COMMUNICATION NETWORK - A grooming apparatus for an optical communication network is disclosed. The apparatus mainly includes a first photoelectric integration unit and an electrical-layer grooming unit. The first photoelectric integration unit includes a wavelength division multiplexing/demultiplexing unit and a photo-electric/electric-photo conversion unit. The wavelength division demultiplexing unit is configured to demultiplex a multi-wavelength optical signal into single-wavelength optical signals. The photo-electric conversion unit is configured to convert the single-wavelength optical signals to single-wavelength electrical signals. The electrical-layer grooming unit is configured to groom the single-wavelength electrical signals. The present invention overcomes the fatal defect of light dispersion, light power estimation, light power adjustment, OSNR limitation for a conventional OADM/ROADM system. Also, the flexibility of the electrical-layer grooming eliminates the wavelength broadcast and multicast issue. The processing of the electrical layer also addresses the wavelength monitoring issue and the wavelength conflict issue.01-28-2010
20090232502VISIBLE LIGHT COMMUNICATION SYSTEM AND OPTICAL WIRELESS LAN DEVICE - A visible light communication system and an optical wireless LAN device are provided, which are capable of establishing a 10 Mbit/s LAN connection by means of an LED lighting unit which integrally has a plurality of LEDs. The optical wireless LAN device 09-17-2009
20120099866System and Method for Operating Transparent Node for WDM Shared "Virtual Ring" Networks - A system and method for a transparent WDM metro ring architecture in which optics enables simultaneous provisioning of dedicated wavelengths for high-end user terminals, while low-end user terminals share wavelengths on “virtual rings”. All wavelengths are sourced by the network and remotely modulated at customer “End Stations” by low cost semiconductor optical amplifiers, which also serve as transmission amplifiers. The transparent WDM metro ring architecture permits the communication of information and comprises a fiber optical feeder ring, at least one fiber optical distribution ring, a network node (NN), at least one access node (AN) said network node and said at least one access node connected via said fiber optical feeder ring and at least one end station (ES) connected via said fiber optical distribution ring to said at least one access node, wherein said user is attached to said at least one end station.04-26-2012
20100129080Method Of Burst Scheduling In A Communication Network - Delay-sensitive burst scheduling in a network is carried out through communications between source and destination nodes. A distributed scheduler at each destination node selects timeslots for burst arrivals from requesting source nodes, irrespective of timeslot selections made by distributed schedulers at other nodes.05-27-2010
20080267628Passive Optical Network System Based on a Wavelength Protection and Protecting Backup Method Thereof - The present invention discloses a passive optical network system based on wavelength protection and the protection backup method thereof. It comprises an optical line terminal (OLT) with two interface circuits, two trunk lines, an optical splitter network, multiple branch lines and optical network units (ONU), each of which is with two interface circuits. The two interface circuits of the OLT transmit downlink optical signals with different wavelengths, while the two interface circuits of the ONU transmit uplink optical signals with different wavelengths. Each trunk line is set with a wavelength division multiplexing (WDM) device and it can only pass the uplink and downlink signals of the connected interface circuits. Each branch line includes a branch optical fiber and a WDM device that is used to transmit two downlink signals to the corresponding interface circuits respectively and meanwhile transmit uplink signals from the two interface circuits as well, so as to form two active/backup bidirectional optical paths between the corresponding interface circuits of the OLT and the ONU. The cost of setting up the system in the present invention is low, but the system can provide hot backup protection for the trunk optical fiber and the OLT.10-30-2008
20120045212OPTICAL AMPLIFICATION DEVICE, COMMUNICATION SYSTEM, AND AMPLIFICATION METHOD - According to an aspect of the invention, an amplification device includes an amplifier configured to amplify a signal light by inputting the signal light and an excitation light to a rare-earth doped amplification medium, a wavelength arrangement monitor configured to acquire wavelength arrangement information indicating a wavelength of the signal light, and a light power controller configured to control power of the input excitation light based on the acquired wavelength arrangement information.02-23-2012
20100189442METHOD FOR THE PROTECTION OF A PASSIVE OPTICAL TRANSMISSION NETWORK AS WELL AS A PASSIVE OPTICAL TRANSMISSION NETWORK WITH A CORRESPONDING PROTECTION MECHANISM - The invention relates to a method for the protection of a passive optical transmission network comprising an optical line terminal (OLT) that is connected to at least one remote node to which a plurality of network termination nodes (ONU) is linked. Between each ONU and the OLT, a bidirectional optical signal transmission can be established, wherein the connection between the OLT and the one or more RNs is realized via a first bidirectional optical transmission route by means of which an optical wavelength-multiplexed signal is transmitted in the downstream direction from the OLT to the one or more RNs and in the upstream direction from the one or more RNs to the OLT. According to the invention, a second bidirectional optical transmission route is provided between the OLT and the one or more RNs, wherein, in the one or more RNs, the wavelength-multiplexed signal is fed in the upstream direction by means of a passive optical splitter unit both to the first optical transmission route and also to the second optical transmission route, and wherein, in the OLT, in the case of the detection of a fault state that suggests a negative effect on the first or second optical transmission route, it is switched to the other corresponding optical transmission route by means of an optical switch unit for transmitting the wavelength-multiplexed signal in the downstream direction and/or for receiving the wavelength-multiplexed signal in the upstream direction. This principle could also be applied analogously, according to the invention, to a ring-shaped linking of several RNs to an OLT. In addition, the invention relates to a passive optical transmission network in which this method is realized.07-29-2010
20120002967ANTENNA SYNCHRONIZATION FOR COHERENT NETWORK MIMO - The invention relates to a method for synchronizing RF antenna signals (01-05-2012
20100111534SYSTEMS AND METHODS FOR CHANNEL POWER OFFSETS FOR MULTI DATA RATE DWDM TRANSMISSION OVER OPTICAL ADD DROP MULTIPLEXERS - The present disclosure provides systems and methods for channel power offsets for multi-rate dense wave division multiplexed (DWDM) transmission over optical add-drop multiplexers (OADMs). The present invention includes algorithms to set power levels of each type of channel in different sections of a fiber system to optimize the performance of that type of channel at the receiver. For example, the present invention can optimize power levels based on different channel modulation formats, bit rates, channel spacings, and the like. Advantageously, the present invention improves the total capacity (bit rate) and reach that channels of a given bit rate can achieve, and maximizes the reach of channels without sacrificing capacity.05-06-2010
20130011139PHOTONIC SYSTEM AND METHOD FOR OPTICAL DATA TRANSMISSION IN MEDICAL IMAGING SYSTEMS - A photonic system and method for optical data transmission in medical imaging system are provided. One photonic system includes a plurality of optical modulators having different optical resonance wavelengths and configured to receive electrical signals representative of a set of data from a medical imaging device. The photonic system also includes an optical waveguide interfacing with the plurality of optical modulators and configured to transmit an amplitude modulated beam of light at different frequencies to selectively modulate the plurality of optical modulators to transmit an encoded beam of light. The photonic system further includes receiver opto-electronics in communication with the optical waveguide configured to decode the encoded beam of light and convert the decoded beam of light into the electrical signals representative of the set of data.01-10-2013
20130011138FLEXIBLE MULTI-BAND MULTI-TRAFFIC OPTICAL OFDM NETWORK - In accordance with some embodiments of the present disclosure a method for receiving and processing an optical orthogonal frequency-division multiplexed signal containing a plurality of traffics comprises receiving the optical orthogonal frequency-division multiplexed signal. The method further comprises down-converting the optical orthogonal frequency-division multiplexed signal into the electrical domain to obtain an electrical signal; filtering the electrical signal to obtain a first portion of the electrical signal containing a first of the plurality of traffics and preprocessing the first portion of the electrical signal in a first parallel preprocessor; filtering the electrical signal to obtain a second portion of the electrical signal containing a second of the plurality of traffics and preprocessing the second portion of the electrical signal in a second parallel preprocessor; and combining the preprocessed first and second portions of the electrical signal to yield a combined electrical signal and demodulating the combined electrical signal.01-10-2013
20120207478OPTICAL TRANSCEIVER INSTALLING CPU AND INTERFACE COMMUNICATING WITH UPPER DEVICE BY MDIO PROTOCOL - An optical transceiver able to communicate with an upper device is disclosed. The optical transceiver distinguishes the peripheral interface from the CPU. The CPU monitors includes MDIO register that stores inner conditions of the optical transceiver. The peripheral interface is coupled with the upper device with the MDIO bus, and the CPU with the parallel bus. The upper device acquires one of the conditions by defining the address of the MDIO register and receiving data through the peripheral interface.08-16-2012
20120008956OPTICAL TRANSMISSION DEVICE, OPERATIONAL WAVELENGTH NUMBER RESTRICTING METHOD, AND PROGRAM - An optical transmission device that is connected to transmission paths of a network, that performs optical communication according to a wavelength division multiplex format and that transmits optical signals over the transmission paths according to path types that have been set to wavelengths of the optical signals, including an upper limit value storage section that stores an upper limit value of the number of operational wavelengths that is the number of wavelengths to which the path types are set; an acceptance section that accepts a changing request that requests that the number of operational wavelengths be changed; and a license determination section that decides the number of operational wavelengths, wherein if the number of wavelengths that has been changed according to the accepted changing request is equal to or smaller than the stored upper limit value, the license determination section newly sets the changed number of wavelengths for the number of operational wavelengths.01-12-2012
20120008955Use of Multiple Shared Wavelength Lockers to Stabilize Transponders in a Wavelength Division Multiplexing (WDM) Network - An apparatus comprising at least one processor configured to receive a wavelength-division-multiplexed (WDM) signal from a remote node, wherein the WDM signal comprises a first channel carrying a first remotely generated signal, a second channel carrying a second remotely generated signal, and a third channel, adapt the WDM signal into a composite WDM signal by: dropping the first remotely generated signal from the first channel; adding a first locally generated signal to the first channel; and adding a second locally generated signal to the third channel, and provide wavelength locking to the first locally generated signal and the second locally generated signal without providing wavelength locking to the second remotely generated signal.01-12-2012
20120014696Novel wavelength allocation for RFoG/GPON/10GPON Coexistence on a single fiber - A method includes conveying a first set of signals including a plurality of first upstream signals within a first upstream wavelength region and a plurality of first downstream signals within a first downstream wavelength region; and conveying a second set of signals including a plurality of second upstream signals and a plurality of second downstream signals, wherein the plurality of second upstream signals and the plurality of second downstream signals are conveyed in a single contiguous wavelength region.01-19-2012
20080219665OPTICAL COMMUNICATION APPARATUS, OPTICAL COMMUNICATION SYSTEM, AND OPTICAL COMMUNICATION CONTROL METHOD - A common unit that transmits or receives control signals is provided in an optical communication apparatus, and the control signals used in communication include different wavelengths from those of main control signals. In this way, it is possible to simplify the structure of an optical communication apparatus, and reduce the manufacturing costs thereof. An optical communication apparatus includes a plurality of main signal transmitting/receiving units and a control signal transmitting/receiving unit that transmits or receives control signals that are used to control communication in the plurality of main signal transmitting/receiving units using different wavelengths from those of the main signals transmitted/received by the main signal transmitting/receiving units.09-11-2008
20120057873OPTICAL COMMUNICATION SYSTEM HAVING LOW LATENCY - Consistent with the present disclosure, an optical communication system is provided in which client data is input to a first node and output from a second node, spaced from the first node, with little delay. In one example, the delay is reduced by including higher order Raman amplifiers that provide a substantially uniform gain along the length of a fiber optic link, thereby reducing the number of EDFAs that may otherwise be installed along the optical fiber link or eliminating such EDFAs entirely. In another example, FEC encoding and decoding are not employed, thereby reducing the delay even further.03-08-2012
20120020667DATA STREAM UPGRADE APPARATUS AND METHOD - A method to transmit and receive significantly larger serial data stream to achieve conformance to the signal interface constraints of a pre-installed transmission system thus minimising bit error rate for both the large serial data streams and the pre-installed streams the method includes the steps of de-serialising an initial incoming signal into M data streams, wherein M>2, each M data stream having a data rate of D/M Gbps, partially serialising and encoding M data streams into K symbol groups where K is an integer greater than or equal to 1, each K symbol group characterized by N concurrent data bits of the N data streams, wherein each N data stream has a data rate of D/(N·K), processing each of the K symbol groups to provide one modulated output signal the K modulated output signals then being transmitted via K channels of an existing wavelength division multiplexing system, so as to enable transmission of significantly large data streams over pre-installed transmission networks.01-26-2012
20100166424COOLERLESS PHOTONIC INTEGRATED CIRCUITS (PICs) FOR WDM TRANSMISSION NETWORKS AND PICs OPERABLE WITH A FLOATING SIGNAL CHANNEL GRID CHANGING WITH TEMPERATURE BUT WITH FIXED CHANNEL SPACING IN THE FLOATING GRID - A coolerless photonic integrated circuit (PIC), such as a semiconductor electro-absorption modulator/laser (EML) or a coolerless optical transmitter photonic integrated circuit (TxPIC), may be operated over a wide temperature range at temperatures higher then room temperature without the need for ambient cooling or hermetic packaging. Since there is large scale integration of N optical transmission signal WDM channels on a TxPIC chip, a new DWDM system approach with novel sensing schemes and adaptive algorithms provides intelligent control of the PIC to optimize its performance and to allow optical transmitter and receiver modules in DWDM systems to operate uncooled. Moreover, the wavelength grid of the on-chip channel laser sources may thermally float within a WDM wavelength band where the individual emission wavelengths of the laser sources are not fixed to wavelength peaks along a standardized wavelength grid but rather may move about with changes in ambient temperature. However, control is maintained such that the channel spectral spacing between channels across multiple signal channels, whether such spacing is periodic or aperiodic, between adjacent laser sources in the thermally floating wavelength grid are maintained in a fixed relationship. Means are then provided at an optical receiver to discover and lock onto floating wavelength grid of transmitted WDM signals and thereafter demultiplex the transmitted WDM signals for OE conversion.07-01-2010
20120301148OPTICAL SIGNAL PROCESSING APPARATUS AND OPTICAL COMMUNICATION SYSTEM - In an optical signal processing apparatus, carrier light propagates through a nonlinear optical medium. An optical combiner optically combines output control light for generating idler light of the carrier light with the carrier light. An optical splitter splits the idler light from the carrier light. A receiver acquires a signal multiplexed on the carrier light from the idler light split by the optical splitter.11-29-2012
20120155880OPTICAL MODULATOR AND OPTICAL MODULATION CONTROL METHOD - An optical modulator includes: a modulator including an optical waveguide provided in a semiconductor substrate having an electro-optical effect and an electrode to apply an electric field depending on a bias voltage and a modulation signal to the optical waveguide; a driver circuit to generate a modulation signal in accordance with an input signal; a superimposer to superimpose a reference signal on the bias voltage, the reference signal having lower frequency than the modulation signal; and a controller to control a bias voltage in a direction orthogonal to a modulation direction of the modulator based on the frequency component of the reference signal extracted from a modulated optical signal generated by the modulator.06-21-2012
20120155879METHOD AND ARRANGEMENT FOR RECEIVING AN OPTICAL INPUT SIGNAL AND TRANSMITTING AN OPTICAL OUTPUT SIGNAL - The present invention relates to a transceiver unit in a PON, Passive Optical Network, for receiving an optical input signal and transmitting an amplitude modulated optical output signal. Further, the present invention relates to a method in a transceiver unit for receiving an optical input signal and transmitting an amplitude modulated optical output signal.06-21-2012
20120063782Method, Circuitry and Apparatus for Outputting a Stable Optical Signal in a Dense Wavelength Division Multiplexing Device During Fast Changes of Operating Conditions - The disclosure relates to a fast and stable method of output wavelength control in a DWDM optical device, and a circuit configured to perform the method. The method and circuit can control of timing and overshoot during conditions of rapid operational changes, such as during power-on or restart of the device. The method and circuit includes optimized APC, TEC and electro-absorption (EA) modulator control hardware and algorithms, to effectively control transient processes. In the present disclosure, software and circuitry based on the method(s) are achieved in part by optimizing APC, EA and TEC control algorithms. The present disclosure combines low-cost methodology and hardware. In combination with hardware/circuit optimization, one can achieve fast turn-on of an optical output signal at a stable wavelength. The method and circuit provides a stable power-up process in which a change of wavelength is small enough to meet DWDM specification requirements, to ensure the elimination and avoidance of crosstalk in adjacent channels in dense wave (sub)systems.03-15-2012
20090180778Forward Discrete/Inverse-Discrete Fourier Transform Device and Method for Optical OFDM Communication and Transmitting and Receiving Apparatus Comprising the Device - Disclosed are a forward discrete/inverse-discrete Fourier transform device and method for optical orthogonal frequency division multiplexing (OFDM) communication and a transmitting and receiving apparatus.The forward inverse-discrete Fourier transform device includes N 1:N splitters for splitting subcarrier signals received from N inputs corresponding to the number of optical frequencies of subcarriers, a phase shift delay array module for shifting phases of the split signals from the 1:N splitters, N N:1 power couplers for coupling signals output from the phase shift delay array module, a time delay array module for performing time delay on optical OFDM symbols from the N:1 power couplers, and an N:1 power coupler for coupling signals output from the time delay array module.07-16-2009
20110103797PLUGGABLE OPTICAL TRANSCEIVER AND METHOD FOR MANUFACTURING THE SAME - A pluggable optical transceiver is disclosed. The transceiver comprises a plurality of OSAs, an optical member and a plurality of inner fibers to couple the optical member with OSAs. The inner fibers each provides an inner connector to couple with one of OSAs. The housing, which installs the OSAs, the optical member and the inner fiber, is made of metal and has a grooves into which the inner fibers is set so as to arrange them orderly.05-05-2011
20110103796BIDIRECTIONAL MULTI-MODE FIBER INTERFACE - A bidirectional interface for multimode optical fiber includes a receive/transmit optical fiber port operable to connect to a multimode optical fiber, a wavelength separating module in communication with the receive/transmit optical fiber port, an optical receiver module in communication with the wavelength separating module and configured to receive optical signals at a first wavelength via the wavelength separating module and the receive/transmit optical fiber port, and an optical transmit module in communication with the wavelength separating module and configured to transmit at a second wavelength via the wavelength separating module and the receive/transmit optical fiber port.05-05-2011
20090220237OPTICAL WAVELENGTH MULTIPLEXING DEVICE, OPTICAL WAVELENGTH DIVIDING DEVICE, OPTICAL WAVELENGTH DIVIDING MULTIPLEXING DEVICE, AND METHOD OF CONTROLLING OPTICAL BAND-PASS FILTER - To equip an optical wavelength dividing multiplexing system with a variable optical band-pass filter, and to provide an apparatus to change the center wavelength and the band width of an optical-band pass filter according to an optical wavelength band to be transmitted, and a method of controlling the apparatus. An optical wavelength multiplexing device 09-03-2009
20100290785OPTICAL WDM TRANSMITTING AND RECEIVING DEVICE AND OPTICAL TRANSCEIVER UNIT FOR THIS DEVICE - An optical transceiver unit for an optical WDM transmitting and receiving device is taught, with a transmitting unit to which a data signal can be fed to a specified channel input port of a multiplexer unit, wherein a separate channel wavelength is allocated to each channel input port, and the transmitting unit can be tuned with respect to optical carrier wavelength across a specified range of wavelengths. The transmitting unit is constructed so that, within the specified range of wavelengths, discrete wavelengths can be set that correspond to the channel wavelengths. In tuning mode, the controller unit can drive the transmitting unit so that the possible channel wavelengths are scanned through. The controller unit evaluates the reception signal fed to it from the receiving unit for whether abort criteria for tuning mode have been fulfilled or not, wherein the scanning process is continued until the abort criteria are fulfilled.11-18-2010
20100092174Differential Inverse Multiplexing Virtual Channels in 40G Ethernet Applications - A system and method are provided for deinterleaving differential inverse multiplexed (DIM) virtual channels in a 40G Ethernet receiver. The method accepts a 10.3125 gigabits per second (Gbps) (10G) Ethernet virtual channel with 64B/86B blocks, including periodic Lane Alignment Marker (LAM) blocks. The 10G virtual channel is deinterleaved into two 5.15625 Gbps (5G) virtual channels by: 1) deinterleaving consecutive blocks from the 10G virtual channel into the 5G virtual channels in an alternating order, and 2) reversing the order of deinterleaving in response to each detected LAM block. Then, the method supplies the 5G virtual channels (i.e. to a MAC module).04-15-2010
20100247099NON-LINEARITY COMPENSATION IN AN OPTICAL TRANSMISSION - A method of transmitting information over a non-linear optical channel includes the step (09-30-2010
20100247100METHOD FOR RECEIVING OPTICAL ORTHOGONAL FREQUENCY-DIVISION MULTIPLEXING SIGNAL AND RECEIVER THEREOF - A method for receiving an optical orthogonal frequency-division multiplexing (OFDM) signal and a receiver thereof are applicable to an optical OFDM system. The receiving method includes the following steps. An optical signal is converted into a digital signal. A symbol boundary of the digital signal is estimated. A guard interval of the digital signal is removed according to the symbol boundary, so as to generate an electrical signal. The electrical signal is converted into a plurality of frequency domain sub-carriers in a fast Fourier transform (FFT) manner. A timing offset is estimated with pilot carriers and frequency domain sub-carriers corresponding to the same symbol period. The estimated symbol boundary is compensated with the timing offset. Each frequency domain sub-carrier includes a plurality of pilot carrier signals. Through the receiving method, the timing offset arisen from chromatic dispersion of an optical fiber is effectively estimated and adopted for compensation.09-30-2010
20090190929OPTICAL ORTHOGONAL FREQUENCY DIVISION MULTIPLEXED COMMUNICATIONS WITH NONLINEARITY COMPENSATION - The present invention discloses a transmitter and receiver for optical communications system, which provide compensation of the optical link nonlinearity. M-PSK modulating is used for data embedding in an optical signal in each WDM channel using orthogonal frequency division multiplexing (OFDM) technique. At the receiver side electrical output signals from a coherent optical receiver are processed digitally with the link nonlinearity compensation. It is followed by the signal conversion into frequency domain and information recovery from each subcarrier of the OFDM signal. At the transmitter side an OFDM encoder provides a correction of I and Q components of a M-PSK modulator driving signal to compensate the link nonlinearity prior to sending the optical signal to the receiver.07-30-2009
20120128361METHOD AND SYSTEM FOR A POLARIZATION MODE DISPERSION TOLERANT OPTICAL HOMODYNE DETECTION SYSTEM WITH OPTIMIZED TRANSMISSION MODULATION - An optical homodyne communication system and method in which a side carrier is transmitted along with data bands in an optical data signal, and upon reception, the side carrier is boosted, shifted to the center of the data bands, and its polarization state is matched to the polarization state of the respective data bands to compensate for polarization mode dispersion during transmission. By shifting a boosted side carrier to the center of the data bands, and by simultaneously compensating for the effects of polarization mode dispersion, the provided system and method simulate the advantages of homodyne reception using a local oscillator. The deleterious effects of chromatic dispersion on the data signals within the data bands are also compensated for by applying a corrective function to the data signals which precisely counteracts the effects of chromatic dispersion.05-24-2012
20120163823CONTINUOUS-MODE WAVELENGTH CONVERSION APPARATUS, BURST-MODE WAVELENGTH CONVERSION APPARATUS, REMOTE TERMINATION APPARATUS AND CENTRAL OFFICE TERMINATION APPARATUS - A continuous-mode wavelength converting apparatus, a burst-mode wavelength converting apparatus, a remote termination apparatus and a central office termination apparatus for converting a burst-mode upstream wavelength signal into a continuous-mode upstream wavelength signal, and thereby transmitting the signal to a long distance and increasing link capacity. The continuous-mode wavelength converting apparatus may convert a received burst-mode upstream electric signal into a continuous-mode upstream electric signal by inserting a first frame at the front of the signal as an indicator of a start of the signal, inserting a second frame at the end of the burst-mode upstream electric signal as an indicator of an end of the signal, and inserting an idle signal into at least one remaining region of the burst-mode upstream electric signal.06-28-2012
20120163824Forward Discrete/Inverse-Discrete Fourier Transform Device and Method for Optical OFDM Communication and Transmitting and Receiving Apparatus Comprising the Device - Disclosed are a forward discrete/inverse-discrete Fourier transform device and method for optical orthogonal frequency division multiplexing (OFDM) communication and a transmitting and receiving apparatus. The forward inverse-discrete Fourier transform device includes N 1:N splitters for splitting subcarrier signals received from N inputs corresponding to the number of optical frequencies of subcarriers, a phase shift delay array module for shifting phases of the split signals from the 1:N splitters, N N:1 power couplers for coupling signals output from the phase shift delay array module, a time delay array module for performing time delay on optical OFDM symbols from the N:1 power couplers, and an N:1 power coupler for coupling signals output from the time delay array module.06-28-2012
20120163821MULTI-WAVELENGTH OPTICAL SOURCE GENERATOR - Provided is a multi-wavelength optical source generator. The multi-wavelength optical source generator includes: a gain part generating a plurality of lights through a plurality of gain waveguides; a reflective part transmitting or reflecting lights provided from each of the plurality of gain waveguides according to a wavelength; and a multiplexing part multiplexing a plurality of lights transmitted and outputted through the reflective part.06-28-2012
20120163822APPARATUS AND METHOD FOR DRIVING WAVELENGTH-INDEPENDENT LIGHT SOURCE - An apparatus for driving a wavelength-independent light source is provided. The apparatus includes a seed light signal generation unit configured to generate seed light signals with one or more wavelengths based on a wavelength identification signal, a wavelength light detection unit configured to detect the wavelength identification signal from the seed light signals, an extraction unit configured to extract wavelength information corresponding to the detected wavelength identification signal and extract a driving condition of a wavelength-independent light source corresponding to the extracted wavelength information, and a driving unit configured to drive the wavelength-independent light source according to the extracted driving condition.06-28-2012
20120163820UPGRADABLE WDM SYSTEM - Consistent with the present disclosure, a wavelength division multiplexed (WDM) optical communication system including on-off-keying (OOK) transmitters, for example, may be upgraded to include advanced modulation format transmitters, such as quadrature phase shift keying (QPSK) transmitters. Rather than replace all the OOK transmitters with QPSK transmitters at once, each OOK transmitter is replaced with a lower rate modulation format transmitter, such as a binary phase shift keying (BPSK) transmitter, as capacity needs increase. The BPSK transmitters supply (BPSK) optical signals that are more tolerant of noise caused by cross phase modulation (XPM) induced by OOK signals. Accordingly, such BPSK optical signals have fewer associated data detection errors in the receiver. Moreover, BPSK modulated optical signals induce little XPM-related noise in co-propagating QPSK modulated optical signals. Thus, once the OOK transmitters have been replaced with the BPSK transmitters, the BPSK transmitters may be replaced with QPSK transmitters or controlled to output QPSK modulated optical signals, as capacity need further increase, and such QPSK modulated optical signals may be transmitted with fewer errors.06-28-2012
20110182584METHOD FOR DATA PROCESSING IN AN OPTICAL NETWORK, OPTICAL NETWORK COMPONENT AND COMMUNICATION SYSTEM - A method for data processing in an optical network includes providing several main wavelengths and processing a subcarrier modulation for the several main wavelengths. An optical network component and a communication system including such an optical network component are also provided.07-28-2011
20120251117Method for Traffic Grooming, Wavelength Assignment and Spectrum Allocation - A method includes determining a line rate selection for a flexible optical wavelength-division-multiplexing WDM network, determining a traffic routing in said network, and determining simultaneously a channel routing, wavelength assignment and spectrum allocation in said network based on an auxiliary graph.10-04-2012
20120251116INTEGRATED OPTICAL-ELECTRONIC INTERFACE IN PROGRAMMABLE INTEGRATED CIRCUIT DEVICE - Systems that provide integrated circuit device circuitry having an integrated optical-electronic interface for high-speed off-device communications are provided. An optical-electronic interface may be incorporated into an integrated circuit device, freeing up some or all of the electrical I/O pins of the integrated circuit device. Transceiver I/O channels may be provided on an integrated circuit device that can be switched between electrical and optical transceiver I/O channels.10-04-2012
20120224856OPTICAL MODULATION DEVICE AND OPTICAL MODULATION METHOD - The present invention has an object to provide an optical modulation device and an optical modulation method that achieve an excellent spectral efficiency with a simple and compact configuration and low power consumption. An optical modulation device according to an exemplary aspect of the present invention includes a CW light source (09-06-2012
20120213521VESTIGIAL PHASE SHIFT KEYING MODULATION AND SYSTEMS AND METHODS INCORPORATING SAME - In general, optical communication systems and methods may implement a vestigial phase shift keying (PSK) modulation format to enable relatively high transmission rates with closer channel spacing and improved signal detection in a WDM optical communication system. A PSK modulated signal may be correlated with a phase shift, for example, using a delay line interferometer (DLI), to generate a vestigial PSK signal, which may be pre-filtered, combined, and transmitted in the WDM system. The correlation with a phase shift compresses and shifts the signal spectrum such that intersymbol interference (ISI) length may be reduced with minimal increase in the bit error rate (BER) when the vestigial PSK signal is detected.08-23-2012
20100061730OPTICAL TRANSMITTING OR RECEIVING UNIT INTEGRATING A PLURALITY OF OPTICAL DEVICES EACH HAVING A SPECIFIC WAVELENGTH DIFFERENT FROM EACH OTHER - An optical unit is disclosed, in which the optical unit provides four optical devices each of which corresponds to a specific wavelength different from each other. In the transmitter unit, the unit includes two optical modules each including two optical devices and one filter unit with a polarization beam filter. The optical beam form two optical devices are combined by the polarization beam filter, while the optical output from the optical modules are combined with the thin film filter.03-11-2010
20120213520Reachability Matrices Spanning Multiple Domains in an Optical Network - A method of providing routes through heterogeneous subsystems in an optical network is disclosed, which includes generating, using a processing device, a reachability matrix based on subnetwork information; and generating, using the processing device, a topology associated with the optical network using the reachability matrix. The method also includes determining, using the processing device, a shortest path through the optical network using the reachability matrix and a cost model graph; and displaying, using a graphical user interface, subsystems associated with the shortest path, regeneration locations associated with the shortest path, wavelengths associated with the shortest path, the topology, and the shortest path. Corresponding apparatus and computer-readable storage media are also disclosed.08-23-2012
20090129780OPTICAL SIGNAL SYNCHRONIZER - One embodiment of the invention provides an optical signal synchronizer having a plurality of optical channel synchronizers. Each optical channel synchronizer receives a respective input wavelength division multiplexing (WDM) signal and processes it to produce a corresponding output WDM signal, in which optical data packets corresponding to different carrier wavelengths are synchronized to each other regardless of the presence or absence of such synchronization in the input WDM signal. The optical signal synchronizer further has an optical multiplex synchronizer that receives the output WDM signals from the optical channel synchronizers and synchronizes them to each other and to an external reference clock without demultiplexing any of them into individual WDM components.05-21-2009
20100046948SYSTEM AND METHOD FOR RECEIVING HIGH SPECTRAL EFFICIENCY OPTICAL DPSK SIGNALS - Apparatus and methods are provided for receiving differential phase-shift keyed (DPSK) optical signals subjected to tight optical filtering, such as may be experienced by 40 Gb/s and 100 Gb/s channels in a dense wavelength division multiplexing (DWDM) communications system with 50 GHz channel spacing. An optical DPSK receiver is described which employs an optical delay interferometer (ODI) demodulator having a free spectral range (FSR) that is larger than the symbol rate (SR) of the DPSK signal to be demodulated. The receiver includes means for introducing an additional power imbalance between the outputs of the ODI demodulator, and the additional power imbalance may be related to the ratio of FSR to SR. The additional power imbalance increases the signal tolerance to tight optical filtering, thereby achieving high spectral efficiency in applications such as DWDM.02-25-2010
20100046950SEEDING WDM PON SYSTEM BASED ON QUANTUM DOT MULTI-WAVELENGTH LASER SOURCE - A seed light source for use in Wavelength Division Multiplexed Passive Optical Network (WDM-PON) includes a multi-channel quantum dot laser for generating a multi-channel seed light comprising a plurality of respective channel seed lights. Each channel seed light corresponds to a respective channel of the WDM-PON.02-25-2010
20100046949Method of Wavelength Alignment for a Wavelength Division Multiplexed Passive Optical Network - Described is a method for controlling the wavelength of a laser in a wavelength division multiplexed (WDM) system. The method includes generating broadband light having a dithered optical power and a wavelength spectrum that includes a plurality of WDM wavelengths. The broadband light is spectrally filtered to generate a spectrally-sliced optical signal having a wavelength spectrum that includes one of the WDM wavelengths. The spectrally-sliced optical signal is injected into a laser and a dithered optical power of the laser is determined. A parameter of the laser is controlled in response to the determination of the dithered optical power to thereby align a wavelength of the laser to the wavelength spectrum of the spectrally-sliced optical signal.02-25-2010
20100008670WAVELENGTH SELECTIVE SWITCH USING PLANAR LIGHTWAVE CIRCUIT TECHNOLOGY - Provided is a wavelength selective switch. The wavelength selective switch includes a first wavelength division multiplexer, an M number of optical switches, an (M+N−1) number of optical combiners, and a second wavelength division multiplexer. The first wavelength division multiplexer receives optical signals of an M number of wavelength channels to divide the received optical signals according to each channel, thereby outputting the divided optical signals. The M number of optical switches changes a path of on an optical signal outputted by an M number of wavelength channels from the first wavelength division multiplexer into one of an N number of output ports. The (M+N−1) number of optical combiners is respectively connected to the N number of output ports of the optical switches. The (M+N−1) number of optical combiners couple the N number of inputted optical signals to one output port. The second wavelength division multiplexer has an (M+N−1) number of input ports and an N number of output ports. The (M+N−1) number of output signals of the optical combiners is connected to the input ports, respectively, and the inputted signals are multiplexed to output the multiplexed signals from any of the N number of output ports.01-14-2010
20120257899ORTHOGONAL BAND LAUNCH FOR REPEATERLESS SYSTEMS - Briefly, in accordance with one or more embodiments, a band of signal carriers is divided into a first band of carriers and a second band of carriers. The carriers in the first band comprise shorter wavelength carriers, and carriers in the second band comprise longer wavelength carriers. Each of the optical sources in the first and second bands of carriers are modulated with an input signal and coupled together via a polarization maintaining coupler. These signals are then combined via a polarization beam combiner wherein the first band has a polarization state that is orthogonal, or nearly orthogonal, to a polarization of the second state.10-11-2012
20090324231TRANSMISSION LINE MONITORING SYSTEM - In a transmission path monitoring system, a first add section adds a first add signal to a first wavelength division multiplexing signal. A first drop section separates a first drop signal from the first wavelength division multiplexing signal. A first loopback section transfers a monitor signal on a first drop optical transmission path onto a second add optical transmission path. A second add section adds a second add signal to a second wavelength division multiple signal. A second drop section separates a second drop signal from the second wavelength division multiplexing signal. A first communication section transmits the first add signal and the monitor signal and receive the second drop signal and the monitor signal.12-31-2009
20090060512Distributed Wavelength Conversion Control for Signaling Protocols - A network component comprising at least one processor configured to implement a method comprising obtaining a wavelength availability information for a path, determining whether to implement a wavelength assignment based on the wavelength availability information, updating the wavelength availability information when the wavelength assignment is to be implemented, and forwarding the wavelength availability information. Also included is a method comprising obtaining a wavelength availability information, comparing a number of wavelengths in the wavelength availability information to a threshold, determining whether to implement wavelength conversion along a path when the number of available wavelengths is less than or about equal to the threshold, and resetting the wavelength availability information when wavelength conversion is to be implemented.03-05-2009
20120263472System and Method for Mitigating Four-Wave-Mixing Effects - In one embodiment, a system includes at least one tone generator, a first transmitter, and a second transmitter. The at least one tone generator is operable to generate a plurality of modulation tones comprising at least a first modulation tone having a first tone frequency and a second modulation tone having a second tone frequency that is different from the first tone frequency. The first transmitter is operable to apply the first modulation tone to a first optical signal such that at least a portion of the first optical signal is divided into one or more sidebands. The second transmitter is operable to apply the second modulation tone to a second optical signal such that at least a portion of the second optical signal is divided into one or more sidebands.10-18-2012
20120082460WAVELENGTH DIVISION MULTIPLEXED OPTICAL COMMUNICATION SYSTEM ARCHITECTURES - Consistent with the present disclosure, data, in digital form, is received by a transmit nodes of an optical communication, and converted to analog signal by a digital-to-analog converter (DAC) to drive a modulator. The modulator, in turn, modulates light at one of a plurality of wavelengths in accordance with the received data. The modulated light is then transmitted over an optical communication path to a receive node. At the receive node, the modulated optical signal, as well as other modulated optical signals are supplied to a photodetector circuit, which receives additional light at one of the optical signal wavelengths from a local oscillator laser. An analog-to-digital converter (ADC) is provided in the receive node to convert the electrical signals output from the photodetector into digital form. The output from the ADC is then filtered in the electrical domain, such that optical demultiplexing of individual channels is unnecessary.04-05-2012
20120082459WAVELENGTH DIVISION MULTIPLEXED OPTICAL COMMUNICATION SYSTEM HAVING VARIABLE CHANNEL SPACINGS AND DIFFERENT MODULATION FORMATS - Consistent with the present disclosure, data, in digital form, is received by a transmit nodes of an optical communication, and converted to analog signal by a digital-to-analog converter (DAC) to drive a modulator. The modulator, in turn, modulates light at one of a plurality of wavelengths in accordance with the received data. The modulated light is then transmitted over an optical communication path to a receive node. At the receive node, the modulated optical signal, as well as other modulated optical signals are supplied to a photodetector circuit, which receives additional light at one of the optical signal wavelengths from a local oscillator laser. An analog-to-digital converter (ADC) is provided in the receive node to convert the electrical signals output from the photodetector into digital form. The output from the ADC is then filtered in the electrical domain, such that optical demultiplexing of individual channels is unnecessary.04-05-2012
20090016727OPTICAL TRANSMISSION APPARATUS - An optical transmission apparatus includes a reception part for receiving a wavelength division multiplexed (WDM) signal reached via optical amplifiers; a measuring part for measuring an optical power level of each wavelength of the WDM signal received by the reception part; a determination part for determining whether an amount of tilt of the WDM signal calculated based on measurement results of the measuring part is suitable or not; an operation part for calculating the tilt correction amount to be applied to tilt correction processing performed by the optical amplifiers if the amount of tilt of the WDM signal is not suitable; and a notification part for notifying the optical amplifiers of the tilt correction amount.01-15-2009
20090016725WAVELENGTHS MULTIPLEXER METHOD AND APPARATUS FOR OPTICAL LOGGING TOOLS - A wavelengths based multiplexer for an optical logging tool method and apparatus comprising a plurality of thin film filter sets and architecture to perform optical wavelength multiplexing without bending an optical fiber within the multiplexer. This enables the multiplexer to be used in a down hole, well logging, tool environment.01-15-2009
20120230694OPTICAL TRANSMITTER - A clock signal from a single reference clock is frequency converted, and the frequency-converted signal is input to an equal-interval-optical-frequency-comb generator and a modulator of an optical modulator. By varying the electric frequency of the clock signal input to the equal-interval-optical-frequency-comb generator, frequency intervals of a frequency comb to be generated can be varied, while by selectively employing a particular optical frequency from among the continuous light beams of the generated frequency comb, a frequency comb having unequal intervals can be generated. It is also possible to vary the modulation rate by varying the clock frequency of a driving signal to be input to the optical modulator. By using a clock signal of a single reference clock, the frequency intervals of the frequency comb and the variation of the modulation rate synchronize with each other.09-13-2012
20110123197COHERENT OPTICAL CHANNEL SUBSTITUTION - In an optical data transmission system, one channel is removed from a group of wavelength division multiplexed optical channels and another channel carrying different information at the same wavelength is inserted in its place. The process occurs by adding an optical signal whose electric field is the difference between the electric field of the new and old channels. The difference calculation takes into account the phase of the incoming WDM channel and phase of the laser source of the difference signal. The method has applications in optical transmission networks as add-drop nodes and optical regenerators, for generation of high bandwidth optical signals, and for secret optical communications.05-26-2011
20120263473NETWORK WITH SOURCELESS CLIENTS - A first node receives a first phase modulated optical signal at a first wavelength from a master node. The first node also transmits a first amplitude modulated optical signal to the master node at the first wavelength using a portion of the first phase modulated optical signal as a light source.10-18-2012
20110038634NETWORK PROTECTION SWITCHING - Servers attached to a data communications network, such as a wavelength division multiplexed network, are made aware of events on the network, such as a protection switch for scheduled maintenance to reduce latency and improve performance, etc. Switching data paths on the data communications network is no longer transparent to the server. A message from the network equipment is received and decoded by a holographic enterprise interface coupled to the server and to a virtual network operation centers. The network equipment reports network switch conditions to the holographic enterprise interface and other connected servers. In response to the network switch conditions, the holographic enterprise interface may automatically reprovision data traffic on the network quickly enough to prevent server timeouts and workload interruptions. The switching is then shown in real time in the virtual network operations center.02-17-2011
20110038633SYNCHRONIZING EVENTS ON A COMMUNICATIONS NETWORK USING A VIRTUAL COMMAND INTERFACE - A virtual network operating center and a virtual command interface synchronize events occurring on a wavelength division multiplexed network with processing events in a connected server. Should a disaster or other interruption of the network occur, the virtual command interface synchronizes events which occur on the network and any attached servers or server clusters with a reference clock coupled to the server. An event queue connected to the virtual command interface preserves the order of messages having a time stamp and compares the timestamps with the reference clock coupled to the server which is used to determine data integrity. The queued events may be encoded as XML device call to update the representation of the network or portions thereof in the virtual network operation center.02-17-2011
20120321319Method of Efficiently and Safely Adding and Deleting Channels in an Amplified Wavelength Division Multiplexing System - An apparatus comprising one or more optical amplifiers coupled to an optical link and configured to amplify a plurality of Wavelength Division Multiplexing (WDM) channels that are transmitted at a plurality of wavelengths on the optical link, and a processor coupled to the optical link and configured to add, delete, or both a plurality of WDM channels in the optical link based on an allowed power ratio indication for the WDM channels, wherein the allowed power ratio indication is calculated based on a plurality of gain change representations for the WDM channels at a plurality of power ratios and on a link budget requirement for the optical link.12-20-2012
20120321320Generation and Direct Detection of Orthogonal Band Multiplexing OFDM Signal with Optical Carriers - The present method includes providing a continuous wave CW optical source with a fixed frequency spacing, separating multiple wavelengths of said CW optical source into different channels, modulating the multiple wavelengths of the CW optical source to generate an OFDM electrical signal with multiple sub-channels and each sub-channel has a channel subcarrier spacing , mixing the OFDM electrical signal with a radio frequency RF sinusoidal signal at a frequency ξf by an electrical mixer and generating a double sideband optical signal, filtering the double sideband signal to generate a single sideband optical signal, combining all channels of the single sideband optical signal, and directly detecting each sub-band of the single sideband optical OFDM signal with a respective detector, the detector converting the optical signal to an electrical signal for digital signal processing.12-20-2012
20110222856All-Optical 2R Regeneration - A method is provided for all-optical regeneration of intensity modulated optical signals. A DFB laser diode is selected such that it has a gain bandwidth comprising the signal wavelength, the signal wavelength being outside the stopband of the DFB laser diode. Furthermore, the DFB laser diode is selected such that it can have a bistable amplification characteristic for the signal wavelength showing a hysteresis with an ascending branch and a descending branch, the ascending branch located at a higher input power level than the descending branch. The DFB laser diode is driven such that it operates in the bistable amplification regime, the descending branch of the hysteresis curve located at an input power level above the lower power level of the optical signal pulses and the ascending branch of the hysteresis curve located at an input power level below the upper power level of the optical signal pulses.09-15-2011
20100226651THREE-WAY OPTICAL DEVICE - A three-way optical device includes a case, a sleeve connected to one of openings of the case, photoelectric elements disposed in one of the openings, and optical filters. Each photoelectric element is associated with an optical signal. Each optical filter is located in the case, corresponding to at least two photoelectric elements, and each optical filter is disposed on an optical path of optical signals associated with the at least two corresponding photoelectric elements. Each optical filter enables the optical signal associated with at least one photoelectric element to penetrate and reflects optical signals associated with the remaining corresponding photoelectric elements, in which the optical signals reflected by the optical filter and penetrating the same optical filter have different wavelengths. The optical signals having different wavelengths associated with the corresponding photoelectric elements are transmitted in a manner of penetrating the optical filters or being reflected by the optical filters.09-09-2010
20100226650Assignment of channel colors in optical networks - A model is provided for optimizing an optical network wherein single links carry multiple signals by using multiple color channels. The routes in the optimized network minimize mid-route color changeovers, reducing the number of nodes requiring optical-electric-optical signal conversion. In the model, the minimized objective function includes terms representing total color miles, terms penalizing changeovers, and terms representing total nodes passed by routes.09-09-2010
20100232797Detection of Data in Signals with Data Pattern Dependent Signal Distortion - A detection system and method may be used to detect data transmitted in a signal with data pattern dependent signal distortion such as intersymbol interference. In general, a detection system and method compares samples of a received signal with stored samples of distorted signals associated with known data patterns and selects the known data patterns that correspond most closely with the samples of the received signal. The detection system and method may thus mitigate the effects of data pattern dependent signal distortion.09-16-2010
20100232796Data Pattern Dependent Distortion Compensation in a Coherent Optical Signal Receiver - A distortion compensation system and method may be used to compensate for data pattern dependent signal distortion in a signal received in a coherent optical signal receiver. In general, the distortion compensation system and method compares a received signal field with stored distorted signal waveforms associated with known data patterns and selects a compensation value associated with the distorted signal waveform that corresponds most closely with the received signal field. The distortion compensation system and method compensates the received signal using the selected compensation value and thus mitigates the effects of data pattern dependent signal distortion.09-16-2010
20100232795Flow-Subcarrier Mapping in Optical Orthogonal Frequency Division Multiplexing - Each of a plurality of data flows is classified as having a respective data flow type, and each data flow is assigned to one of a plurality of subcarrier groups, based on the data flow's type, wherein each subcarrier group comprises a respective plurality of subcarriers. First data flows assigned to a first subcarrier group are transmitted exclusively on respective subcarriers in the first subcarrier group, and second data flows assigned to a second subcarrier group are transmitted together on all of the subcarriers in the second subcarrier group.09-16-2010
20120087668METHOD AND DEVICE FOR GENERATING AND RECEIVING OOFDM SIGNAL, AND WAVELENGTH-DIVISION MULTIPLEXING SYSTEM - Embodiments of the present invention relate to the field of communications, and in particular, disclose a method and a device for generating and receiving an OOFDM signal, and a wavelength-division multiplexing system. The method for generating an OOFDM signal includes: converting a channel of serial high-speed data to N channels of parallel low-speed data; performing modulation mapping on the N channels of parallel low-speed data respectively to obtain N channels of information sequences; expanding the N channels of information sequences to 2N+2 channels of information sequences which have a Hermitian symmetric structure; performing inverse Fast Fourier Transform on the 2N+2 channels of information sequences, and then performing parallel-to-serial conversion to obtain an OFDM baseband signal; performing digital-to-analog conversion on the OFDM baseband signal to obtain an OFDM analog signal; and modulating the OFDM analog signal to an optical carrier to obtain an OOFDM signal.04-12-2012
20120087666BIDIRECTIONAL WAVELENGTH DIVISION MULTIPLEXED-PASSIVE OPTICAL NETWORK - Provided is a bidirectional WDM-PON. The bidirectional WDM-PON includes an optical comb generator, an amplifier, an optical de-interleaver, a downstream signal generator, an upstream signal generator, an upper circulator, and a lower circulator. The optical comb generator generates multi-wavelength light. The amplifier amplifies the multi-wavelength light. The optical de-interleaver receives the amplified multi-wavelength light to divide the received light into an odd wavelength train and an even wavelength train, and outputs the odd and even wavelength trains. The downstream signal generator receives the odd wavelength train to generate a downstream signal. The upstream signal receiver receives an upstream signal. The upper circulator determines a delivery path of the odd wavelength train and the downstream signal. The lower circulator determines a delivery path of the even wavelength train and the upstream signal.04-12-2012
20120087665METHOD AND APPARATUS FOR PROVIDING A ROUTE RECOMMENDATION - A method and apparatus for providing a route recommendation are disclosed. For example, the method obtains network topology information, wherein the network topology information comprises a plurality of underlying subnetwork types for a network. The method creates a cost model for the network, and receives a request from a user for a connection to be supported by the network. The method provides the route recommendation for supporting the connection by applying the cost model.04-12-2012
20120328296Optical Spectrum Recovery - The invention is directed to systems and methods for re-arranging optical spectrum utilization so that unallocated portions of the spectrum may be made contiguous. Rearrangement of optical spectrum is accomplished by moving a channel from its initial spectral location to a targeted spectral location by reserving additional spectrum for that channel that at least includes the targeted spectral location, shifting the channel to the targeted location and then collapsing the reserved spectrum around the targeted location to cover the minimal required spectrum for the channel allocation of the channel. In some cases, a secondary channel can be used as an alternate source to carry user traffic while the first channel is shifted to the targeted location.12-27-2012
20100202776Optical Modulation Signal Generating Device and Optical Modulation Signal Generating Method - There is provided an optical modulation signal generating device in which an operation speed is not limited by a relaxation oscillation frequency of a laser, and high-speed modulation and long-distance transmission can be performed. The optical modulation signal generating device converts a signal from a signal source into an optical signal and outputs the optical signal to a transmission medium having frequency dispersion. The optical modulation signal generating device includes an optical source (08-12-2010
20080279557WDM-PON SYSTEM USING SELF-INJECTION LOCKING, OPTICAL LINE TERMINAL THEREOF, AND DATA TRANSMISSION METHOD - Disclosed are a wavelength division multiplexing-passive optical network (WDM-PON) system using self-injection locking, an optical line terminal thereof, and a data transmission method. A wavelength division multiplexing-passive optical network (WDM-PON) system according to an aspect of the invention includes an optical line terminal. The optical line terminal includes a reflector that is installed at the input side of a multiplexer and reflects an optical signal having a predetermined wavelength, and a light source that generates a multimode optical signal to transmit the generated multimode optical signal to the multiplexer through the reflector, receives reflected light by the reflector, and oscillates at a wavelength of the received reflected light. According to the aspect of the invention, it is not necessary to separately control the temperature of a light source for a downstream signal, and stable communication can be performed by collectively controlling wavelengths of downstream channel optical signals for downstream channels through temperature control of the multiplexer.11-13-2008
20130016976EXTENDED CAVITY FABRY-PEROT LASER ASSEMBLY CAPABLE OF HIGH SPEED OPTICAL MODULATION WITH NARROW MODE SPACING AND WDM OPTICAL SYSTEM INCLUDING SAME - An extended cavity Fabry-Perot laser assembly provides relatively narrow mode spacing while allowing relatively high speed optical modulation. The extended cavity Fabry-Perot laser assembly generally includes an exit reflector physically separated from a laser emitter (e.g., a gain chip) to extend the lasing cavity and narrow the mode spacing while maintaining a relatively small gain region in the laser emitter capable of higher speed optical modulation. The extended cavity Fabry-Perot laser assembly may be used in a multi-channel transmitter in a wavelength division multiplexed (WDM) optical system that selects a channel wavelength for the transmitter from among multiple channel wavelengths emitted by the laser assembly. The narrow mode spacing may be less than a WDM channel width, and more specifically, may be less than a channel passband of an arrayed waveguide grating (AWG) or other filter used to select the channel wavelength.01-17-2013
20110158650OPTICAL NETWORK - An optical network and a method of provisioning an optical network are described. The optical network includes a first passive optical network optical line terminal arranged to transmit a first optical signal at a first wavelength, coupled to a first port of a first optical filter arrangement, and a second passive optical network optical line terminal arranged to transmit a second optical signal at a second, different wavelength, coupled to a second port of the first optical filter arrangement. An optical coupler is connected between the second passive optical network line terminal and the second port of the first optical filter arrangement, for coupling a plurality of optical signals at a predetermined set of wavelengths from a third optical line terminal into the second port. A passive optical distribution node, for connection to a plurality of optical network terminations, is coupled to a third port of the first optical filter arrangement for distribution of optical signals between the optical line terminals and the plurality of optical network terminations. The first optical filter arrangement is arranged to pass optical signals at the first wavelength between the first port and the third port and to block optical signals at the second wavelength and the predetermined set of wavelengths between the first port and the third port, and the first optical filter arrangement is further arranged to pass optical signals at the second wavelength and the predetermined set of wavelengths between the second port and the third port and to block optical signals at the first wavelength between the second port and the third port. The second optical signal is at a faster rate than the first optical signal, and the second wavelength and the predetermined set of wavelengths are within an amplification band of a doped fibre amplifier.06-30-2011
20130170835OPTICAL TRANSMITTER DEVICE - An optical transmitter device includes a laser source, a driving circuit, and an optical modulator. The driving circuit is connected to the laser source. The driving circuit includes a thermistor configured for compensating the temperature variation of the laser source to stabilize the frequency of a laser beam output from the laser source. The optical modulator is configured for modulating the laser beam to form a plurality of second laser beams which have different frequencies.07-04-2013
20080232806TRANSPONDER UNIT, TRANSPONDER UNIT CONTROL APPARATUS, TRANSPONDER UNIT CONTROL METHOD AND RECORDING MEDIUM RECORDING TRANSPONDER UNIT CONTROL PROGRAM - A transponder includes a CDR section that extracts clocks from an input signal, an oscillating section that can output various frequencies to the CDR section, a frequency instruction processing section that instructs the oscillating section to output an arbitrary frequency, a detection processing section, and a frame processing section control section. The detection processing section determines whether the frequency output from the oscillating section and an input signal synchronize in frequency or not in response to an instruction by the frequency instruction processing section, and detects a synchronization frequency. The frame processing section control section operates a frame processing section based on the synchronization frequency detected by the detection processing section.09-25-2008
20100086307PLANAR LIGHTWAVE CIRCUIT - Consistent with the present disclosure optical interleaver and deinterleaver circuits are integrated onto a substrate. The inputs to the interleaver and the outputs of the deinterleaver are each coupled to a corresponding variable optical attenuator (VOA) and optical tap, which are also provided on the substrate. The optical taps supply a portion of the output of each VOA to a corresponding photodetector. A control circuit, which is coupled to the photodetector, in turn, supplies a control signal to each VOA based on the output of the photodetector. Accordingly, optical multiplexing and demultiplexing components, as well as monitoring and power regulating components are provided on the same chip. Such a chip may be compact, relatively inexpensive, and has reduced power consumption compared to optical multiplexer and demultiplexer equipment including discrete components.04-08-2010
20080226296Optical transmitter with suppressing wavelength deviation at begging of operation - An optical transmitter is disclosed in which the wavelength deviation occurred at the turning on from the disabled state to the enabled state by the negating of the Tx_Disable command is suppressed. The optical transmitter includes a semiconductor laser diode (LD) and an automatic temperature controller (ATC) circuit to drive the thermoelectric cooler (TEC). When the transmitter receives the Tx_Disable to start up the operation of the LD, a pulsed signal is generated in synchronizing with the transition of the Tx_Disable signal to momentarily enhance the cooling capacity of the TEC in order to compensate the increase of the temperature of the LD by the self heating, which prevents the output wavelength of the transmitter from deviating.09-18-2008
20080226295LIGHT MODULATING APPARATUS - A light modulating apparatus which is to be used in a transmission system using wavelength division multiplexing has: a signal generating section for producing a transmission signal and the like; a first light modulating section for modulating light emitted from a light source, on the basis of the transmission signal; a variable phase shifter which changes a phase of a light quantity control signal; a second light modulating section for modulating a light signal emitted from the first light modulating section, on the basis of an output of the variable phase shifter; a branching section for branching a light signal emitted from the second light modulating section, into an output light signal and an electric signal; and an analysis controlling section for sampling the electric signal, controlling the variable phase shifter on the basis of sampled data, and adjusting a timing of the modulation in the second light modulating section.09-18-2008
20130177315PHASED ANTENNA ARRAY WITH ELECTRO-OPTIC READOUT CIRCUIT WITH MULTIPLEXING AND MLL AND RELATED METHODS - A phased antenna array includes an array of antenna elements, and an electro-optic (EO) readout circuit coupled to the array of antenna elements. The EU readout circuit includes an optical source including a mode locked laser (MLL) configured to generate an optical carrier signal having beam carrier wavelengths, an EO modulator configured to modulate a signal from an antenna element based upon the optical carrier signal, a first WDM coupled downstream from the EO modulator, and optical-to-electrical converters coupled downstream from the first WDM. The first WDM is configured to multiplex each modulated beam carrier wavelength to a respective optical-to-electrical converter.07-11-2013
20130177316OPTICAL COMMUNICATION SYSTEM, AND TRANSMITTER AND RECEIVER APPARATUS THEREFOR - An optical communication system having a transmitter in which a pair of optical signals having different frequencies are modulated using a duobinary encoding scheme, and then multiplexed using polarization division multiplexing. Advantageously, the frequency difference between the two signals can be less than the data rate conveyed by each signal, resulting in a narrow spectral bandwidth, while still allowing demultiplexing at a receiver using simple bandpass filters and without the need of any form of polarization tracking. A receiver has a beam splitter for splitting the received optical signal into two portions which are each directed, via respective bandpass filters centred at slightly different frequencies, to respective detectors. Advantageously, the frequency difference between the frequencies at which the bandpass filters are centred can be less than the data rate of a detected signal. The receiver does not require any polarization tracking or balancing, and accordingly is straightforward to implement07-11-2013
20080219666OPTICAL LINE TERMINAL ARRANGEMENT, APPARATUS AND METHODS - A wavelength division multiplexed optical communication system includes a plurality of optical line terminals which may be part of separate in service networks, each having a line interface and an all-optical pass-through interface including a plurality of pass-through optical ports, and each also including a plurality of local optical ports which are connectable to client equipment and an optical multiplexer/demultiplexer for multiplexing/demultiplexing optical wavelengths. The optical multiplexer/demultiplexer may include one or more stages for inputting/outputting individual wavelengths or bands of a predetermined number of wavelengths, or a combination of bands and individual wavelengths. At least one of the pass-through optical ports of an optical line terminal of one network may be connected to at least one of the pass-through optical ports of an optical line terminal of another network to form an optical path from the line interface of the optical line terminal of the one network to the line interface of the optical line terminal of the another network to form a merged network. The use of such optical line terminals allows the upgrading and merging of the separate networks while in service.09-11-2008
20130101296OPTICAL TRANSMITTER, OPTICAL TRANSMISSION METHOD, AND OPTICAL TRANSMISSION/RECEPTION SYSTEM - An optical transmitter includes: a selection circuit; a signal processing circuit; an optical modulator; and a control circuit. The selection circuit selects signal components on the sides of the maximum and minimum values in a multivalued electrical signal for modulation of a transmitting signal. The signal processing circuit generates a multivalued electrical signal into which the transmitting signal is converted by a combination of a superimposed signal that a low-frequency wave is superimposed on the signal components and a signal having a plurality of intermediate amplitude values on which the low-frequency wave is not superimposed. The optical modulator modulates a carrier light on the basis of the multivalued electrical signal. The control circuit controls the reference amplitude value or amplitude of the multivalued electrical signal on the basis of the low-frequency components contained in a modulated optical signal.04-25-2013
20130101295COMPACT TUNABLE OPTICAL OFDM SOURCE - An optical transmitter includes first and second optical single sideband modulators. The first optical single sideband modulator is configured to receive an input optical signal and produce a first frequency-shifted optical signal. The first frequency-shifted optical signal has a first frequency shift with respect to the input optical signal. The second optical single sideband modulator is configured to receive the first frequency-shifted optical signal and produce a second frequency-shifted optical signal. The second frequency-shifted optical signal has a second different frequency shift with respect to the input optical signal.04-25-2013
20130121700METHOD, APPARATUS AND SYSTEM FOR TRANSMITTING SERVICE DATA ON OPTICAL TRANSPORT NETWORK - The embodiments of the present disclosure provide a method, an apparatus, and a system for transmitting service data on an optical transport network. The method includes: mapping the service data into a low order flexible optical channel data unit (ODUflex); multiplexing multiple low order ODUflexs into a high order ODUflex; adding a forward error correction (FEC) overhead into the high order ODUflex to generate a flexible optical channel transport unit (OTUflex); and splitting the OTUflex into multiple data channel signals, and modulating the data channel signals to orthogonal frequency division multiplexing subcarriers to send the orthogonal frequency division multiplexing subcarriers. The foregoing solution provides OTUflexs. Therefore, the network adapts service data for flexibly variable line rates of the optical transport network through a control protocol, and transmits service data of different rates to meet the development requirements of higher-rate optical transport networks.05-16-2013
20110268445OPTICALLY VARIABLE FILTER ARRAY APPARATUS - In an optically variable filter array apparatus, WDM-signal light beams of m channels ranging in wavelength from λ11-03-2011
20090175622METHOD FOR ALLOCATING UPSTREAM TRANSMISSION BANDWIDTH IN WDM-EPON - Disclosed is a method fox allocating upstream transmission bandwidth so as to prevent Inter-Scheduling Cycle Gaps (ISCGs) from occurring in an N number of Optical Network Units (ONUs) by using an m number of wavelength channels for upstream transmission in a Wavelength-Division Multiplexing (WDM)-Ethernet Passive Optical Network (EPON). The method includes: grouping the ONUs to be allocated each of the m number of wavelength channels; and performing a Dynamic Bandwidth Allocation (DBA) algorithm in order for the grouped ONUs to efficiently use allocated wavelengths and time slots, thereby allocating each wavelength channel. Accordingly, by using a scheme of managing ONUs by each group, it is possible to more efficiently allocate bandwidth than the online scheduling scheme. As compared with the offline scheduling scheme, ISCGs caused by bandwidth allocation do not occur.07-09-2009
20110211838LOW-COST WDM SOURCE WITH AN INCOHERENT LIGHT INJECTED FABRY-PEROT LASER DIODE - The present invention discloses a low-cost light source for optical transmission systems and optical networks based on wavelength-division multiplexing (WDM) technology. A light source in accordance with the present invention is implemented by externally injecting a narrow-band incoherent light into a Fabry-Perot laser diode (F-P LD). After injection of narrow-band incoherent light, the output of F-P LD becomes wavelength-selective rather than multi-mode and the output wavelength of F-P LD coincide with the peak wavelength of the injected incoherent light.09-01-2011
20080199181OPTICAL TRANSMISSION APPARATUS WITH OPTICAL AMPLIFIERS - An optical transmission apparatus including an optical amplifier for providing a high-power optical amplifier on the receive side, in which a wavelength of pumping light for an optical amplifier on the transmission side is suitably shifted to be different from a wavelength of pumping light for an optical amplifier on the receive side, pumping optical power for the optical amplifier on the transmission side is not all consumed in a doped fiber in amplification process, and remnant pump light that was left surplus is added by a wavelength multiplex coupler to the pumping light for the optical amplifier on the receive side, thereby enhancing a gain and light output without an increase in output power of the pumping light used for the optical amplifier on the receive side.08-21-2008
20130148970RECEIVER OPTICAL MODULE FOR RECEIVING WAVELENGTH MULTIPLEXED OPTICAL SIGNALS AND METHOD TO ASSEMBLE THE SAME - A receiver optical module to facilitate the assembling is disclosed. The receiver optical module includes an intermediate assembly including the optical de-multiplexer and the optical reflector each mounted on the upper base, and the lens and the PD mounted on the sub-mount. The latter assembly is mounted on the bottom of the housing; while, the former assembly is also mounted on the bottom through the lower base. The upper base is apart from the bottom and extends in parallel to the bottom to form a surplus space where the amplifying circuit is mounted.06-13-2013
20130148971DIRECT DETECTION OF OPTICAL ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING (OFDM) SIGNALS - Techniques for timing synchronization in an optical orthogonal frequency division multiplexing (OOFDM) system includes providing a time-domain training symbol having a symmetric distribution and producing the training symbol by transmitting a real-valued PN sequence on each subcarrier under the OOFDM. The training sequence includes an initial value, followed by an odd length palindromic sequence of values.06-13-2013
20100028002PASSIVE OPTICAL NETWORK SYSTEM EMPLOYING SUB-CARRIER MULTIPLEXING AND ORTHOGONAL FREQUENCY DIVISION MULTIPLE ACCESS MODULATION SCHEMES - Implementations of the present principles include methods, systems and apparatuses for transmitting data through a sub-carrier multiplexing and orthogonal frequency-division multiple access passive optical network. In accordance with aspects of the present principles, a plurality of optical network units are assigned electrical carrier frequency bandwidths that are narrower than a system capacity bandwidth. Modulation of optical waves transmitted between an optical line terminal and each optical network unit is conducted on different orthogonal sub-carrier frequencies within the assigned bandwidths such that sampling of said orthogonal sub-carrier frequencies is limited to the assigned electrical carrier frequency bandwidths. The waves are thereafter received and demodulated for the extraction of data.02-04-2010
20130148969OPTICAL TRANSCEIVER SYSTEM - An optical transceiver system includes a transmitter transmitting out a first light beam with a first wavelength, a receiver receiving a second light beam with a second wavelength; an optical fiber transmitting the first light beam and the second light beam; and a light guide member. The light guide member includes a lens block having a first side surface facing toward both the transmitter and the receiver, and a second side surface facing toward the optical fiber. A first lens portion and a second lens portion formed on the first side surface for optically coupling the respective transmitter and receiver, a third lens portion formed on the second side surface for optically coupling the optical fiber, and a wavelength divisional multiplexer embedded in the lens block. The wavelength divisional multiplexer receives and divides the first light beam and the second light beam.06-13-2013
20100290786Branching Configuration Including Separate Branching Unit and Predetermined Wavelength Filter Unit and System and Method Including the Same - In general, a branching configuration used in a wavelength division multiplexed (WDM) optical communication system includes a branching unit (BU) and a separate predetermined wavelength filter (PWF) unit. The PWF unit may include wavelength selective elements (e.g., filters) for providing a desired wavelength allocation and may also include optical connections (e.g. optical couplers) for coupling the allocated wavelengths between trunk and branch paths in the WDM system. The PWF unit is physically separate from an associated BU but coupled adjacent the BU.11-18-2010
20100316384Point-to-multipoint high data rate delivery systems from optical node in HFC systems over existing and advanced coaxial network - Methods and apparatus are described for transmitting and receiving data. A method includes a process of transferring data over a coaxial network at a bandwidth above 1000 MHz, wherein the process of transferring data transfers the data between an optical node and a plurality of cable modems of a hybrid fiber-coaxial cable network. An apparatus includes a data transfer system which sends and receives data over a coaxial network at a bandwidth above 1000 MHz, wherein the data transfer system is located at an optical node of a hybrid fiber-coaxial cable network.12-16-2010
20100316383WAVELENGTH DIVISION MULTIPLEXED-PASSIVE OPTICAL NETWORK APPARATUS - Provided is a wavelength division multiplexed-passive optical network (WDM-PON) apparatus. The WDM-PON includes an optical source unit, an optical mux, and a chirped Bragg grating. The optical source unit generates an optical signal. The optical mux receives the optical signal from the optical source unit through one end of the optical mux, multiplexes the optical signal, and outputs the multiplexed optical signal. The chirped Bragg grating is connected to the other end of the optical mux. The chirped Bragg grating again reflects the optical signal having passed the optical mux to re-input a certain portion of the optical signal into the optical mux and the optical source unit. The optical mux performs a spectrum slicing on the re-inputted optical signal and operates the optical source unit using a channel wavelength of the optical mux as a main oscillation wavelength.12-16-2010
20100316382Ramen Backpumped Near-Zero Dispersion CWDM System and Method - A system includes an optical transmitter portion, an optical fiber, an optical receiver portion, a laser portion and a combiner portion. Optical signals may be launched by the optical transmitter portion at very low power levels to avoid Raman-induced interactions between the co-propagating signals along the optical fiber. The laser portion and the combiner portion may apply a back-pumped laser signal to the optical fiber. The back-pumped laser signal provides a Raman gain that amplifies the co-propagating signals to a minimum power level such that the optical receiver portion can detect the co-propagating signals within a predetermined acceptable carrier-to-noise ratio.12-16-2010
20130183040SYSTEM, METHOD AND FIBER-OPTIC TRANSCEIVER MODULE FOR BANDWIDTH EFFICIENT DISTORTION-TOLERANT TRANSMISSIONS FOR HIGH-BIT RATE FIBER OPTIC COMMUNICATIONS - According to one embodiment of the invention, fiber optic communications method is described. The method comprises a first operation of dynamically identifying frequencies at which spectral nulls occur in a signal received via an optical fiber, and thereafter, segregating communications over the optical fiber into a set of inter-null bands defined by the spectral nulls.07-18-2013
20110311230OPTICAL BUS - An optical bus. Optical sub-assemblies are used to connect lengths of optical fiber to form a single optical fiber that is a bus. A master transceiver may be connected to one end of the fiber and nodes can be connected to the optical sub-assemblies. Each optical sub-assembly includes a center fiber with a mirror that enables each connector to reflect optical signals out of the fiber and that enables a node to launch optical signals on the optical bus. The optical bus can also be connected with a second transceiver that may be used to deliver optical power to the attached nodes. Some nodes include two optical subassemblies to enable bidirectional communication on the optical bus.12-22-2011
20110311229OPTICAL TRANSMISSION/RECEPTION MODULE - An optical transmission/reception module including a filter holder on which filter mount surfaces for mounting wavelength division multiplexing filters and light wavelength band limiting filters are formed and in which a hole for guiding a light signal is formed in each of the filter mount surfaces incorporated into a housing. The wavelength division multiplexing filters and the light wavelength band limiting filters are mounted to the filter mount surfaces formed on the filter holder, respectively.12-22-2011
20130188956COMMUNICATION DEVICE AND COMMUNICATION METHOD - A communication device includes a signal correcting unit that performs signal correction on an electric signal indicating information to be transmitted to reduce signal deterioration occurring in transmission of the electric signal; a conversion unit that converts the electric signal subjected to the signal correction into a digital signal on which information indicating the signal correction performed by the signal correcting unit is superimposed; and a light-emitting element that emits light in accordance with the digital signal converted by the conversion unit.07-25-2013
20130188955OPTICAL TRANSMISSION DEVICE AND OPTICAL TRANSMISSION METHOD - There is provided an optical transmission device including: a packet disassembler configured to disassemble a packet into a plurality of signals having a different wavelength; an amplifier configured to amplify, for each of the wavelength, each signal into which the packet is disassembled by the packet disassembler, based on a correction value set for each wavelength; and a multiplexer configured to multiplex the respective signals amplified by the amplifier so as to transmit a packet generated by multiplexing the respective signals.07-25-2013
20130188957METHOD AND DEVICE FOR ADJUSTING FILTERING BANDWIDTH OF AN OPTICAL DEVICE - A method for adjusting a filtering bandwidth of an optical device includes: acquiring a modulation bandwidth of a first optical signal and s modulation bandwidth of a second optical signal, where the first optical signal is an optical signal input into a first wavelength channel of an optical device, the second optical signal is an optical signal input into a second wavelength channel of the optical device, and the second wavelength channel is adjacent to the first wavelength channel; comparing the modulation bandwidth of the first optical signal with the modulation bandwidth of the second optical signal; and according to a result of comparing the modulation bandwidth of the first optical signal with the modulation bandwidth of the second optical signal, adjusting a filtering bandwidth of at least one wavelength channel of the first wavelength channel and the second wavelength channel.07-25-2013
20130195459METHOD AND APPARATUS FOR FIBER NON-LINEARITY MITIGATION08-01-2013
20130195460WAVELENGTH PATH REALLOCATION METHOD AND UPPER LAYER PATH REALLOCATION METHOD - A wavelength path reallocation method in a path reallocation apparatus for reallocating a wavelength path set in a communication network, including: a wavelength path designing step in which a wavelength path designing unit designs a reallocation destination wavelength path by performing calculation such that the number of use frequency regions in the communication network becomes smaller than a corresponding value before reallocation; and a wavelength path setting step in which a wavelength path setting unit changes a reallocation target wavelength path to the reallocation destination wavelength path by using free wavelength.08-01-2013
20100014862Mach-Zehnder Light Modulator, Mach-Zehnder Light Modulating Method, Optical Transmitter, Light Modulator, Optical Transmitting Apparatus, and Optical Receiving Apparatus - A phase modulator (22) modulates, based on an electrical signal (Sa), the phase of one of optical signals of an input optical signal branched by a light branching circuit (21). Then, a phase modulator (23) performs phase modulation in a smaller amount and opposite polarity as compared to the phase modulator (22) based on an electrical signal (Sc) obtained by delaying the inverse logic signal (Sb) of the electrical signal (Sa) by a predetermined delay time τ shorter than the transient response time of the phase modulator (22) or the rise and fall times of the electrical signal (Sa). A light multiplexing circuit (24) multiplexes the optical signal obtained by the phase modulator (23) with the other optical signal of the input optical signal, thereby outputting a pulse-like output optical signal (36).01-21-2010
20120087667AWG SUPPORTING MULTIPLE FREQUENCY BANDS AND CHANNEL PLANS - Roughly described, an AWG has two or more inputs and multiple outputs. By selecting the angular spacing among the inputs, and by designing the different inputs to address different orders of the waveguide array, the device can be designed such that the inputs will carry frequency bands having any desired center frequency spacing and any desired same or different channel spacing. For example a dual input device can be designed such that one input carries C-band channels and the other input carries L-band channels, and both have channel spacings that match or substantially match the ITU grid.04-12-2012
20120093515Method, Apparatus, and System for a Self-Seeded External Cavity Laser for Dense Wavelength Division Multiplexing Applications - A network apparatus comprising an optical gain medium, a wavelength division multiplexing (WDM) filter coupled to the optical gain medium, and a Faraday Rotator Mirror (FRM) coupled to the WDM, and wherein the optical gain medium, the WDM filter, and the FRM are coupled by single mode fibers to form a self-seeded external cavity laser for a DWDM wavelength channel.04-19-2012
20120093514BI-DIRECTIONAL CWDM (OR DWDM) TRANSMISSION SYSTEM USING SINGLE WAVELENGTH BI-DIRECTIONAL TRANSCEIVERS - The present invention provides a bi-directional CWDM (or DWDM) transmission system using SWBiDi transceivers for a continuous and simultaneous communication in both directions comprising an optical link fiber, first n CWDM (or DWDM) SWBiDi transceivers at a first end of the optical link fiber, second n CWDM (or DWDM) SWBiDi transceivers at a second end of the optical link fiber, a first optical CWDM (or DWDM) MUX/DEMUX between first n CWDM (or DWDM) SWBiDi transceivers and the optical link fiber, and a second optical CWDM (or DWDM) MUX/DEMUX between second n DWDM SWBiDi transceivers and the optical link fiber.04-19-2012
20130209106OPTICAL TRANSMISSION SYSTEM, MULTI-CORE OPTICAL FIBER, AND METHOD OF MANUFACTURING MULTI-CORE OPTICAL FIBER - An optical transmission system includes: a multi-core optical fiber having a plurality of core portions. Signal light beams having wavelengths different from each other are caused to be input to adjacent core portions of the plurality of core portions. The adjacent core portions are the most adjacent to each other in the multi-core optical fiber.08-15-2013

Patent applications in class Wavelength division or frequency division (e.g., Raman, Brillouin, etc.)

Patent applications in all subclasses Wavelength division or frequency division (e.g., Raman, Brillouin, etc.)