Patent application number | Description | Published |
20080199189 | COLORLESS OPTICAL DEMODULATOR FOR DIFFERENTIAL QUADRATURE PHASE SHIFT KEYING DWDM SYSTEMS - A colorless optical DQPSK demodulator and system operating over multiple, equally-spaced DWDM channels with fixed optical delays—capable of demodulating DQPSK within signals within DWDM communications wave bands on ITU grids using delay interferometers having fixed free spectral range at 20 GHz or 25 GHz. | 08-21-2008 |
20080253768 | High Bit Rate Packet Generation with High Spectral Efficiency in an Optical Network - Optical packets are generated by generating a first optical beam with a first wavelength and a second optical beam with a second optical beam. The first optical beam is modulated with a payload signal and then filtered to reduce the bandwidth of the signal. The second optical beam is modulated with a label signal. The filtered modulated first optical beam and modulated second optical beam are combined to generate a dual-wavelength optical beam. | 10-16-2008 |
20080267630 | ORTHOGONAL FREQUENCY DIVISION MULTIPLE ACCESS (OFDMA) BASED PASSIVE OPTICAL NETWORK (PON) ARCHITECTURE AND ITS EXTENSION TO LONG DISTANCE - A passive optical network (PON) device, system and method include an optical line terminal (OLT) receiver configured to receive multiple signals at different wavelengths simultaneously and enable multiple transmitters to operate at the same time during one upstream time slot. The optical line terminal employs Orthogonal Frequency Division Multiple Access (OFDMA) to transparently support a plurality of applications and enable dynamic bandwidth allocation among these applications where the bandwidth is allocated in two dimensional frequency and time space. | 10-30-2008 |
20090059351 | DEMODULATOR SYSTEM AND METHOD USING MULTILEVEL DIFFERENTIAL PHASE SHIFT KEYING - A demodulator and demodulation method includes an optical coupler configured to receive an input signal. The optical coupler couples the signal to an even number of branches. Each branch including at least one interferometer configured to split, combine and interfere with an optical signal from one of within the branch or from another branch. A common optical delay is disposed on one of every two branches between the optical coupler and the interferometer of the branch. | 03-05-2009 |
20090162066 | Intra-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 |
20090251345 | PHOTONIC FILTER BANK FOR HIGH-SPEED ANALOG-TO-DIGITAL CONVERSION - An analog to digital converter (ADC) structure and method includes a photonic filter bank having at least two filters. The at least two filters are configured to create a corresponding spectral tributary from an input signal at a target rate, and the at least two filters are configured to exhibit orthogonality properties between respective tributaries. An optical/electrical (O/E) converter is coupled to each of the at least two filters in a respective spectral tributary to convert an optical input to an electrical output. An analog to digital converter (ADC) is coupled to each of the O/E converters in a respective spectral tributary to sample the electrical output at a fraction of a target rate and to convert a sampled analog electrical output into a digital signal. A synthesis filter is coupled to each of the ADCs in a respective spectral tributary to reconstruct the input signal digitally at the target rate. | 10-08-2009 |
20090274460 | DIFFERENTIAL DELAY RECEIVER USING CROSS-POLARIZATION INTERFEROMETER FOR POLMUX-DPSK SYSTEM - A differential delay detection system and method includes an optical splitter to split an incoming optical signal between a first path and a second path. The first path includes a cross-polarization interferometer configured to separately generate polarization independent outputs using split paths and to generate cross-polarization interference outputs, and a polarization demultiplexer configured to combine the polarization independent outputs and the cross-polarization interference outputs from the cross-polarization interferometer with updated coefficients received from the second path to remove the cross-polarization mixed signals, The second path includes a training signal receiver configured to compute the updated coefficients and output the updated coefficients to the polarization demultiplexer. | 11-05-2009 |
20090285577 | Optical 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 |
20100028001 | Generation 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 |
20100028002 | PASSIVE 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 |
20100232789 | Modified Michelson Interferometer Structure for Inter-Symbol Interference-Suppressed Colorless DPSK Demodulation - An optical device includes an interferometer for a received optical differential phase shift keying DPSK signal, and an equalizer integrated with the interferometer in a manner for reducing from optical filtering effects an interference by signal bits of the DPSK signal with signal bits of a contiguous DPSK signal. The interferometer is a Michelson delay interferometer type, but can also be a Mach-Zehnder delay interferometer type on fiber, waveguide or other optical structure. The equalizer is a Fabry-Perot type equalizer, but can be a ring resonator type or a fiber based equalizer. | 09-16-2010 |
20100232803 | Integrated Equalizer and Michelson Interferometer Structure for Inter-Symbol Interference-Suppressed colorless DPSK demodulation - An optical device includes an interferometer for a received optical differential phase shift keying DPSK signal, and an equalizer integrated with the interferometer in a manner for reducing from optical filtering effects an interference by signal bits of the DPSK signal with signal bits of a contiguous DPSK signal. The interferometer is a Michelson delay interferometer type, but can also be a Mach-Zehnder delay interferometer type on fiber, waveguide or other optical structure. The equalizer is a Fabry-Perot type equalizer, but can be a ring resonator type or a fiber based equalizer. | 09-16-2010 |
20100260500 | MULT9-DEGREE WAVELENGTH CROSS-CONNECT USING BIDIRECTIONAL WAVELENGTH SELECTIVE SWITCH - A modular wavelength cross connect node for use in a dense wavelength division multiplexing network exhibiting low cost and improved performance by employing a bidirectional wavelength selective switch in a main optical path and using optical circulators to share any common ports. | 10-14-2010 |
20110020003 | Generating 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 |
20110069954 | On Improved Optical Network Apparatus Having Optical Line Terminal Blade Protection with 1-to-N Redundancy and No-Service-Interruption - There is provided an optical network apparatus having interconnected processing gigabit passive optical network G-PON blades, a protection blade, and controller blade, the regular blades and protecting blade having a higher layer processing and switching interface to a G-PON media access control MAC coupled to PHY including serializer and de-serializer modules that are connected to respective interface modules, the improvement including a protecting 1:N signal drive and a protecting N:1 signal select driver coupled between the interface module and serializer and de-serializer modules of the protecting blade, respectively, for protecting connection to the interface module of the protecting blade. The improvement further includes a processing 1:N signal driver and a processing N:1 signal select driver coupled between the interface module and serializer and de-serializer modules of the processing G-PON blade, respectively, for protecting connection to the interface module of the processing G-PON blade and a 1:2 signal driver and 2:1 signal select driver in the interface module for providing an alternative connection to the protection blade. | 03-24-2011 |
20110286746 | Transponder Aggregator Without Wavelength Selector for Colorless and Directionless Multi-Degree ROADM Node - A method for transponder optical channel selection of optical signals from a transponder aggregator includes choosing wavelength division multiplexing channels to be dropped from a transponder aggregator receiving optical input signals, splitting all dropped wavelength division multiplexing channels into at least one transponder having a coherent receiver and transmitter, and tuning a local oscillator laser of the coherent receiver to a wavelength of one of the all dropped wavelength division multiplexing channels for selecting one of the all dropped wavelength division multiplexing channels. | 11-24-2011 |
20120069856 | Rate Selection for Channel Selection in Flexible WDM Networks - An inventive method implemented in a communications system includes obtaining a first data rate in a flexible wavelength division multiplexing FWDM network and applying a recursive rate selection for determining a given data rate from the obtained first data rate such that a required spectrum over the FWDM network for the given data rate is minimized, the first data rate being lower than the given data rate. | 03-22-2012 |
20120070148 | K-alternate Channel Selection for the Routing, Wavelength Assignment and Spectrum Allocation in Flexible Optical WDM Networks - A method implemented in an optical flexible wavelength division multiplexing FWDM network includes finding a first channel out of available channels with sufficient spectrum on a given route out of available channels in an optical FWDM network; finding a second channel at a lower wavelength out of the available channels for minimizing total spectrum on the given route; selecting a channel out of the available channels on K-distinct shortest routes; and finding line rates of channels using a predetermined channel selection. | 03-22-2012 |
20120070150 | Greedy 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 |
20120251117 | Method 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 |
20150046592 | NETWORK FOLLOWED BY COMPUTE LOAD BALANCING PROCEDURE FOR EMBEDDING CLOUD SERVICES IN SOFTWARE-DEFINED FLEXIBLE-GRID OPTICAL TRANSPORT NETWORKS - A method for providing cloud embedding using Network followed by Compute Load Balancing (NCLB) by mapping one or more virtual links over one or more physical links while balancing network resources, and mapping one or more virtual nodes over one or more physical nodes while balancing different types of computational resources. | 02-12-2015 |