Inventors list

Assignees list

Classification tree browser

Top 100 Inventors

Top 100 Assignees


FAULT RECOVERY

Subclass of:

398 - Optical communications

Patent class list (only not empty are listed)

Deeper subclasses:

Class / Patent application numberDescriptionNumber of patent applications / Date published
398002000 Bypass inoperative element 148
398007000 WDM 21
398008000 TDM 7
398006000 In a repeater system 5
20090202237System and Method for Fault Identification in Optical Communication Systems - A system and method for fault identification in optical communication networks. One or more repeaters in the system includes a loop back path that couples an output a first amplifier for amplifying signals carried in a first direction through a repeater to an input of a second amplifier for amplifying signals carried in a second direction through said repeater. Fault analysis is conducted using loop gain data associated with test signals transmitted on the first or second paths and returned on the opposite path through the loop back paths.08-13-2009
20130064538DATA RELAY APPARATUS AND FUNCTION CONTROL METHOD THEREFOR - A data relay apparatus R (e.g., one included in an ONU) that performs data transfer from one port to another port reduces power consumption by performing control to limit a receive function of a receiving unit 03-14-2013
20090116834OPTICAL TRANSMISSION APPARATUS AND RESTART CONTROL METHOD - An apparatus comprises an optical level controller for autonomously controlling an optical device such that an optical level of the supplied optical signal becomes an objective level, and a controlled variable storer for storing a controlled variable in storage if a restart is required, the optical level controller providing the controlled variable to control the optical signal, wherein the optical level controller starts the control of optical device after the restart while the controlled variable stored in the storage by the controlled variable storer is set at an initial value.05-07-2009
20100310252OPTICAL COMMUNICATION - This concerns a protected long-reach PON having a plurality of terminals connected to a distribution network that is fed by both a main and back up feed, each feed including a head end and a repeater. The back up head end had access to a ranging table with data previously obtained by the main head end, thereby speeding up the switch over in the event of a fault with the main feed. In one embodiment, the repeater has a virtual ONU therein, allowing the back up repeater to be ranged by the back up head end, thereby yet further speeding up the ranging procedure. The main and back up repeaters are sufficiently equidistant from the distribution network to allow the back up head to perform normal scheduling without performing a ranging operation on each of the terminals, even if the different terminals transmit at slightly different wavelengths. This is achieved using the ranging information obtained with regard to the back up repeater.12-09-2010
20110164873OPTICAL REPEATER, OPTICAL TRANSMISSION APPARATUS, REFLECTION ABNORMALITY DETECTION METHOD AND REFLECTION ABNORMALITY RECOVERY DETERMINATION METHOD - An output light intensity monitor unit of an optical repeater monitors an output light of an output point of the optical repeater. A reflected light intensity monitor unit monitors a reflected light returning from an optical fiber to the output point, An optical fiber transmission line loss from the apparatus output point to an optical fiber open end and a light intensity emitted from the open end are estimated from a monitored reflected light intensity, and a reflection abnormality detection threshold for detecting the reflection abnormality if the light intensity emitted from the open end exceeds a reference light intensity is prescribed. An output light intensity lowering amount and a reflection abnormality recovery threshold are prescribed from an output light intensity monitored at the apparatus output point and the reflected light intensity so that an open end output light intensity may be lowered to the reference light intensity.07-07-2011
Entries
DocumentTitleDate
20120163795METHOD AND DEVICE FOR INDICATING CLIENT SIGNAL FAIL - The present invention discloses a method for indicating client signal fail in an optical transport network, including: adding CSF indication bits to an Optical Channel Payload Unit k (OPUk) or/and OPUk-Xv multiframe to indicate whether a client signal is failed; detecting the CSF indication bits of a PSI in the received OPUk or/and OPUk-Xv multiframe, and when the number of continuously detected CSF indications exceeds a preset threshold, indicating to perform a link protection switch. The present invention also discloses an apparatus for implementing the above method. The present invention can avoid the case of APS fail due to the too long CSF time delay; the indication method is simple and the implementation is convenient; and a plurality of CSF indications are used in the multiframe, thus the indication is more flexible.06-28-2012
20130077959DE-MAPPING METHOD AND DEVICE FOR OPTICAL TRANSPORT UNIT FRAME - The disclosure discloses a de-mapping method and a device for an Optical Transport Unit (OTU) frame. The method includes: setting a receiving reference clock and a de-mapping path according to a highest priority of an OTU frame mapping mode of a local device (S03-28-2013
20090175616Automatic power restoring method and optical communication system - The present invention provides an automatic power restoring method capable of reliably detecting continuity by the dissolution of a line fault, to restore the optical power, even in a structure including an optical amplification medium on an optical transmission path and an optical communication system using the method. To this end, in an optical communication system to which the automatic power restoring method of the invention is applied, a pilot signal having a low transmission rate, a wavelength of which is set based on loss wavelength characteristics obtained by combining loss wavelength characteristics of an optical fiber used for the optical transmission path and loss wavelength characteristics of the optical amplification medium on the optical transmission path, is transmitted and received between an optical transmitting station and an optical receiving station when a line fault occurs, and a detection of continuity is thus performed. According to the result of the continuity detection, the power state at the occurrence of line fault is automatically restored to the power state at a time of normal operation.07-09-2009
20090154917PHOTONIC INTEGRATED CIRCUIT DEVICE AND ELEMENTS THEREOF - A photonic integrated circuit (PIC) device is described. The PIC device includes a set of optical transceivers including optical transmitters and optical receivers, and an embedded optical interconnect mesh operatively associated with the set of optical transceivers and structured to enable at least one of the following network architectures: a star network architecture, a bus/broadcast network architecture, and a ring network architecture. Related apparatus and methods are also described.06-18-2009
20090154916Method and Apparatus for GPON GEM Error Correction Implementation - A method and a device of enhancing data integrity using hash function for data transmission over an optical network are disclosed. The device includes a hash circuit, a lookup circuit, a vector circuit, and a correcting circuit. The hash circuit is capable of performing a hash function and configured to generate a hash value in response to a value of header error correction (“HEC”) encapsulated in a gigabit passive optical network (“GPON”) frame. The lookup circuit is capable of obtaining a data entry from a lookup table in a memory in accordance with the hash value. While the vector circuit generates an error vector in response to the data entry, the correcting circuit corrects an error or errors in the header portion of a data structure encapsulated in the GPON frame.06-18-2009
20100027988FRAME PROCESSING APPARATUS, OPTICAL RECEIVING APPARATUS, OPTICAL TRANSCEIVING APPARATUS, OPTICAL TRANSMISSION SYSTEM, AND FRAME PROCESSING CONTROLLING METHOD - The technique for improving the efficiency in use of power resources while maintaining the received signal quality that satisfies the requirement during a system operation is disclosed. The frame processing apparatus disclosed in the present case includes: a frame processing unit which performs frame processing on an input signal in the designated error processing mode; and a controlling unit which receives the monitoring result relating to the signal quality of the input signal and performs switching control of the designation of the above error processing mode in the frame processing unit based on the received monitoring result.02-04-2010
20120219282OPTICAL TRANSMISSION SYSTEM AND OPTICAL TRANSMISSION METHOD - An optical transmission system transmits an optical signal of multi-level modulation. In a transmitter module, a data string in a specified frame is rearranged into a plurality of logical lanes. A lane ID, which specifies in what logical lane out of the plurality of logical lanes a start of the data string is arranged, is assigned to a non-scrambled area in an overhead portion of the frame. The lane ID corresponding to one of the plurality of logical lanes is different from the lane IDs corresponding to the other remaining logical lanes. The optical signal is generated using the data string rearranged into the plurality of logical lanes. In a receiver, the lane ID is detected according to a majority method. The inversion of bits and the swapping of lanes are detected using the lane ID and compensated.08-30-2012
20110013903OPTICAL COMMUNICATION - A protected passive optical communications system (01-20-2011
20090269051METHOD OF CONTROLLING OPTICAL OUTPUT POWER AND PASSIVE OPTICAL NETWORK SYSTEM USING THE SAME - Provided are an optical output power control method that provides optical communication without harming the human body even when a transmission line is cut or no optical network unit (ONU) accesses a communication system, and a passive optical network (PON) system using the method. In the method, an optical signal having a predetermined period is transmitted when an optical communication system is in an abnormal state, wherein the predetermined period includes a laser-on time interval in which the optical signal has a normal power level and a laser-off time interval in which the optical signal is off or has a power level lower than the normal power level, so that the optical communication system performs optical communication without harming the human body even during the abnormal state.10-29-2009
20120237198FIBER OPTIC ROTARY JOINTS, METHODS PRACTICED THEREBY, AND FIBER OPTIC DEVICES - This invention provides a fiber optic rotary joint (09-20-2012
20110033180Method and Appartus for Regulating Rogue Behavior in Optical Network Transmission Devices - A method and apparatus for regulating rogue behavior in optical transmission devices. The apparatus, for example, may be implemented in one or more of the ONTs in a PON. The ONT includes an optical transmitter that may be disabled by a command generated by the ONT itself if rogue behavior is detected or suspected. To detect rogue behavior, at least one output indictor, such as LBC or MPC, is monitored during one or more monitoring windows. If monitoring indicates that the optical transmitter is transmitting more than a pre-determined threshold, a suspect rogue flag is set, for example in an I2C register. The register is read, preferably a number of successive times, and a determination is made whether to disable the optical transmitter. In some embodiments, the OLT is queried as part of this determination. The disability may be permanent, until a manual service operation, for example, or temporary.02-10-2011
20090129770LIGHT TRANSMISSION DEVICE AND METHOD OF SETTING LIGHT INPUT BREAK DETECTION THRESHOLD VALUE - According to an aspect of an embodiment, in a light transmission device for switching a light transmission path for receiving an optical signal from a currently used system to a backup system when the light level of light input from a light transmission path of a currently used system becomes substantially equal to or less than a light input break detection threshold value which serves as a reference for detecting a light input break. The light transmission device includes light level measuring means for measuring the light level of the light input from the light transmission path of the currently used system, and light input break detection threshold value setting means for detecting only the light level of accumulated noise of the light level measured by the light level measuring means and setting the detected light level as the light input break detection threshold value.05-21-2009
20100054731METHODS AND SYSTEMS FOR THE HIERARCHICAL MESH RESTORATION OF CONNECTIONS IN AN AUTOMATICALLY SWITCHED OPTICAL NETWORK - The present disclosure describes methods and systems for the hierarchical mesh restoration of connections in an ASON or the like. These methods and systems provide a mesh restorable OTN server layer that carries an aggregate of mesh restorable SONET/SDH SNCs, without designating SONET/SDH/OTN hand-off ports or work/protect lines. Server layer SNCs are terminated on Virtual Trail Termination Points (VTTPs) on the NEs. These VTTPs maintain all of the attributes of physical Trail Termination Points (TTPs). The server routing protocol creates physical TTP interfaces at the server layer, and the server layer advertises bandwidth to the client layer routing protocol. A failure in the server layer results in the mesh restoration of an aggregate line, holding off the release of the individual client SNCs. Only when the server layer cannot restore are these individual client SNCs released.03-04-2010
20110076008Optical code division multiplexing communication system and method for correcting failure of the same - An OCDM communication system and a method for correcting failure of the same are provided. In the system, encoders and decoders are provided respectively for channels. Each encoder, including an SSFBG, encodes an optical signal using a code value determined according to distance between adjacent unit fiber Bragg gratings in the SFFBG. Each decoder, including an SFFBG, generates a received optical signal by decoding the encoded signal using a code value determined in the same manner. A set temperature of each encoder and decoder is calculated and a corresponding control signal is generated based on average power and error rate detection signals of each received optical signal. The temperature of each encoder or decoder is individually adjusted according to the control signal, which makes equal the code values of an encoder and decoder of a channel in which average power of a received signal has changed or error rate thereof is excessive.03-31-2011
20110142437Header error control protected ten gigabit passive optical network downstream frame synchronization pattern - An apparatus comprising an optical line terminal (OLT) configured to couple to a plurality of optical network units (ONUs) and transmit a plurality of downstream frames to the ONUs, wherein each of the downstream frames comprises a plurality of forward error correction (FEC) codewords and a plurality of additional non-FEC encoded bytes that comprise synchronization information that is protected by Header Error Control (HEC) code. An apparatus comprising a processing unit configured to arrange control data, user data, or both into a plurality of FEC codewords in a downstream frame and arrange a physical synchronization sequence (PSync), a superframe structure, and a Passive Optical Network-identifier (PON-ID) structure in a plurality of additional non-FEC encoded bytes in the downstream frame, and a transmission unit configured to transmit the FEC codewords and the additional non-FEC encoded bytes in the downstream frame within a 125 microsecond window.06-16-2011
20100014852CSMA/CD OPTICAL INTERCONNECT SCHEME - A method of detecting transmission collisions in an optical data interconnect system including a transmitting node, a plurality of receiving nodes, and one or more remaining nodes connected through an optical data channel. The method includes initiating a data transmission of a data signal from the transmitting node over the optical data channel, transmitting a first collision detect signal from the transmitting node throughout a duration of the data transmission where the first collision detect signal is transmitted over an optical detection channel corresponding to the transmitting node, monitoring at the transmitting node of the optical data interconnect system for a predetermined period of time, where the optical data interconnect system further includes a plurality of optical collision detection channels corresponding to each of the plurality of receiving nodes and the one or more remaining nodes, and identifying a transmission collision when a second collision signal is received through one of the plurality of optical collision detection channels at the transmitting node during the predetermined period of time.01-21-2010
20090317073SYSTEMS AND METHODS FOR ETHERNET EXTENSION AND DEMARCATION - The present invention provides Ethernet extension and demarcation functionality through a Multi-Source Agreement (MSA) pluggable transceiver in a customer or remote device. The pluggable transceiver is configured to frame an Ethernet client signal and to provide OAM&P functionality, such as with G.709 framing. The pluggable transceiver operates within existing multi-source agreement (MSA) specifications. Accordingly, the pluggable transceiver can operate in any customer device compliant to the MSA specifications. Additionally, the framing and OAM&P functionality are transparent to the customer device, but instead utilized by a service provider for demarcation functionality, eliminating the requirements for external demarcation equipment and for external transponders.12-24-2009
20120033963OPTICAL SUBSCRIBER TERMINATING DEVICE, PON SYSTEM, AND ABNORMALITY DETECTING METHOD - An ONU that receives a discovery gate transmitted by an OLT in a predetermined cycle, returns a response signal in response to the discovery gate, and receives a unicast frame transmitted to the ONU by the OLT having received the response signal, comprising: a received frame detecting unit that detects whether a signal received from the OLT is a discovery gate or a unicast frame; and an erroneous emission detecting unit that detects an abnormal emission state, based on a result detected by the received frame detecting unit.02-09-2012
20120294603Method and System for Service Protection - A method and system for service protection based on the Dual Node Interconnection (DNI) protection structure in the transport network are provided. When creating a DNI protection group, a plurality of services are configured in one direction, wherein one is a working service, and the others are protection services; the multiple services have the same add node and drop node, but not exactly the same passed interconnection nodes; on each interconnection node of the add ring, two services in the DNI protection group through the local node to the drop ring are adapted as two services in a 1+1 protection group; on the drop node, services in the DNI protection group are adapted as two services in a 1+1 protection group transmitted from two directions of the drop ring; when a fault occurs, said interconnection node and drop node execute switching according to the 1+1 protection protocol.11-22-2012
20080317461Automatic power restoring method and optical communication system - The present invention provides an automatic power restoring method capable of reliably detecting continuity by the dissolution of a line fault, to restore the optical power, even in a structure including an optical amplification medium on an optical transmission path and an optical communication system using the method. To this end, in an optical communication system to which the automatic power restoring method of the invention is applied, a pilot signal having a low transmission rate, a wavelength of which is set based on loss wavelength characteristics obtained by combining loss wavelength characteristics of an optical fiber used for the optical transmission path and loss wavelength characteristics of the optical amplification medium on the optical transmission path, is transmitted and received between an optical transmitting station and an optical receiving station when a line fault occurs, and a detection of continuity is thus performed. According to the result of the continuity detection, the power state at the occurrence of line fault is automatically restored to the power state at a time of normal operation.12-25-2008
20090052889OPTICAL NETWORK TERMINAL BACKUP BATTERY CENTRALIZED MONITORING AND VOLTAGE ALERT - An optical network terminal (ONT) battery backup unit (BBU) battery voltage alert system (BVAS). This alert is provided as a supplement to an audio alarm which sounds when the backup battery is discharging because that alarm may not be heard in sufficient time if the alarm is remotely located relative to its customer, e.g., in the customer's basement or outside. A battery monitoring facility, located in a telecommunication service provider's centralized serving office, or remotely located elsewhere, monitors the voltage of each of a plurality of batteries deployed in customers' premises within the geographical area served by that centralized serving office. That battery monitoring facility receives packets via a communication network from each such customer's premises, each of those packets representing a battery voltage measurement. That battery monitoring facility stores these on-going measurements thereby creating a trending database to point to any potential future battery failures. The battery monitoring facility alerts a particular customer via the communication network when its battery is about to fail by email/text, fax, telephone or other similar mechanism.02-26-2009
20110222846SHARED PHOTONIC MESH - A network element of an optical communications network. The network element comprises an electronic router for forwarding traffic between a set of client access ports and a plurality of I/O ports. A respective EO interface is coupled to each one of the plurality of I/O ports. Each EO interface terminates a respective optical channel. A directionally independent access (DIA) node is configured to selectively route each optical channel between its respective EO interface and a selected one of at least two optical fiber links of the optical communications network.09-15-2011
20090245781APPARATUS AND METHOD FOR DETECTING TIMESLOT CONFLICT BETWEEN OPTICAL NETWORK UNITS IN OPTICAL COMMUNICATION NETWORK - The objective of the present invention is to provide a solution for detecting timeslot conflict between Optical Network Units (ONUs) in an Optical Line Terminal (OLT). When all ONUs are deactivated and there is still any light signal in the upstream, each ONU is notified to switch off the power supply of its transmitter one by one to detect whether there is any failure ONU; when all ONUs are deactivated and there is no light signal in the upstream, the failed ONU can be located through ranging the ONUs separately. The solution can be implemented through software update, without affecting the intrinsic hardware design.10-01-2009
20120141116METHOD AND DEVICE FOR RECOVERING OTUK FRAME, AND SYSTEM FOR TRANSPORTING OTUK FRAME - A method for recovering an OTUk frame includes: receiving an optical signal sent by using a method of multi-lane distribution from the OTUk frame to an interface of an optical module; converting the optical signal into an electrical signal, performing electrical equalization and demodulation on the electrical signal, and recovering multi-lane data from the demodulated signal; aligning and rearranging the data on each lane, according to a lane sequence identifier included in an overhead frame header of the data on each lane; and recovering the OTUk frame according to the aligned and rearranged data. According to the present invention, lane rearrangement is performed by detecting the lane sequence identifier, and the recovery of the OTUk frame is achieved. Therefore, a training sequence overhead does not need to be additionally introduced, and the influence on the system performance is avoided.06-07-2012
20120141115APPARATUS AND METHOD FOR CLEARING A FAULT CONDITION OVER A FIBRE CHANNEL PATH - A method for clearing a fault condition at a target device is disclosed herein. In selected embodiments, such a method includes detecting a fault condition at a target device and receiving N instructions before the fault condition is cleared, where the N instructions are unexecutable due to the fault condition. N fault condition indicators are transmitted in response to the N instructions. Clearing of the fault condition is detected when the fault condition no longer exists. Acknowledgments corresponding to the fault condition indicators are received, where each acknowledgment indicates that one of the fault condition indicators has been received. A fault clear indicator is transmitted only after both all N fault condition indicators have been received and clearing of the fault condition has been detected. A corresponding system and computer program product are also disclosed herein.06-07-2012
20110058806System and Method for Distributed Fault Sensing and Recovery - A method and system for distributed fault sensing and recovery in a communication system. A master controller is provided in each cable station of the system. Each master controller receives local alarms, e.g. aggregated alarms from associated shelf controllers, and may receive remote alarms from other master controllers. Local and remote alarms are compared to a profile provisioned in the master controllers for determining whether to perform a fault recovery function.03-10-2011
20090208200SYNCHRONOUS OPTICAL SIGNAL GENERATING DEVICE AND SYNCHRONOUS OPTICAL SIGNAL GENERATING METHOD - A synchronous optical signal generation device includes: an optical phase detector that compares the phase of a reference optical signal with a phase of an optical beat signal to generate a phase error signal; a shaping mechanism that shapes the phase error signal; and a voltage controlled optical signal generator that generates an optical beat signal based on the shaped phase error signal and that outputs the optical beat signal while feeding the optical beat signal back to the phase detector.08-20-2009
20090324214Method, Apparatus and System for Handling Fiber Line Fault - A method for handling a fiber line fault is provided. The method includes: loading, by a station, an indication signal carrying alarm suppression information onto an optical signal to be output to a downstream fiber of the station upon detection of a fault on upstream fiber line; keeping in a normal working status, by a downstream station upon a receipt of the optical signal with the indication signal. The various embodiments of the present disclosure suppress alarms from downstream amplifier stations which are not adjacent to the failure link and further suppress APR or APSD procedures according to the alarms.12-31-2009
20100220994Self-correcting wavelength collision avoidance system - A method includes detecting wavelength collision including identifying a pair or pairs of ONTs that transmit the colliding wavelengths and recovering from collision wherein wavelengths of the pair or pairs of ONTs that cause collisions are re-adjusted to eliminate the collision.09-02-2010
20110008039FORWARD ERROR CORRECTION (FEC) ENABLED PHOTONIC INTEGRATED CIRCUIT (PIC) CHIPS WITH MULTIPLE SIGNAL CHANNELS - A forward error correction (FEC) communication device that includes a transmitter photonic integrated circuit (TxPIC) or a receiver photonic integrated circuit (RxPIC) and a FEC device for FEC coding at least one channel with a first error rate and at least one additional channel with a second error rate, wherein the first error rate is greater than the second error rate. The TxPIC chip is a monolithic multi-channel chip having an array of modulated sources integrated on the chip, each operating at a different wavelength, wherein at least one of the modulated sources is modulated with a respective FEC encoded signal. The TxPIC also includes an integrated wavelength selective combiner for combining the channels for transport over an optical link.01-13-2011
20110026917METHODS AND APPARATUS FOR FAST AND ENERGY-EFFICIENT LINK RECOVERY IN A VISIBLE LIGHT COMMUNICATION (VLC) SYSTEM - A visible light communication (VLC) device is provided for use in a VLC system. The VLC device detect a trigger condition indicating a failure of a VLC link associated with first allocated resources used to communicate with a second VLC device. In response to the detection, the VLC device terminates on the first allocated resources transmission of data to the second VLC device and transmits a fast link recovery (FLR) signal using the first allocated resources. The VLC device receives a fast link recovery response (FLR RSP) signal indicating the second VLC device received the FLR signal and, in response, the VLC device resumes transmission of data to the second VLC device.02-03-2011
20090214198OPTICAL TRANSMITTER - A optical transmitter includes a light device provided a driving current and for emitting light on the bases of the driving current; a light measure for measuring an output light level of the light device; a controller for controlling the driving current to the light device and for changing the measured output light power level into a set output light power level of the light device; a current measure for measuring a level of the driving current to the light device; an abnormality detector for detecting an aged deterioration of the light device on the bases of the current level of the driving current by the current measure and the measured output light power level by the light measure; and an adjuster for reducing the set output light power level in the controller when the abnormality detector detects the aged deterioration of the light device.08-27-2009
20110044683FAST PROTECTION SCHEME FOR PASSIVE OPTICAL NETWORK - The present invention relates to a method and devices for fast protection of an optical network system, in particular for a Passive Optical Network (PON), such as a Gigabit-capable Passive Optical Network (GPON). In the method, it is detected that the communication from a first optical network device is lost. Switching of functionality is initiated from a first optical line termination device to a second optical line termination device, and a control message is sent from the second optical line termination device to the first optical network device such that the first optical network device is prevented from moving into initial state. Furthermore, the method comprises determining and setting timing settings for the first optical network device.02-24-2011
20110076009OPTICAL AXIS ADJUSTING APPARATUS AND OPTICAL AXIS ADJUSTING METHOD - An optical axis adjusting apparatus for an optical device includes a drive unit moving an optical component through which communication light emitted from a light source passes, a plate member disposed facing the optical component, the plate member allowing light to transmit through the plate member and reflecting light to the optical component, a photographing unit disposed on a back side of the plate member, taking an image irradiated with the light transmitted through the plate member, and a control section controlling the drive unit to move the optical component based on the image and information on optical characteristics of the light reflected by the plate member.03-31-2011
20090136229Method and System for Transmitting Information in an Optical Communication System Using Distributed Amplification - A method and system for transmitting information in an optical communication system includes modulating a non-intensity characteristic of an optical carrier signal with a data signal to generate an optical information signal. The optical information signal is transmitted over an optical link. The optical information signal is amplified over a length of the optical link with a co-launched amplification signal traveling in the optical link in a same direction as the optical information signal.05-28-2009
20110164872FAST CONVERGENCE ON CHILD LINK FAILURES AND WEIGHTED LOAD BALANCING OF AGGREGATE ETHERNET/SONET BUNDLES - A network device provides a selector list that includes indices of child nexthops associated with the network device, where each of the child nexthops is associated with a corresponding child link provided in an aggregated bundle of child links. The network device also receives an indication of a failure of a child link in the aggregated bundle of child links, and removes, from the selector list, an index of a child nexthop associated with the failed child link. The network device further receives probabilities associated with the child links of the aggregated bundle of child links. Each of the probabilities indicates a probability of a packet exiting the network device on a child link. The network device also creates a distribution table based on the probabilities associated with the child links, and rearranges values provided in the distribution table.07-07-2011
20110255858Polarization Demultiplexing Using Independent Component Analysis - Systems and methods of polarizaton demultiplexing are disclosed. One such method receives a transmitted polarization-multiplexed optical signal The polarization-multiplexed has multiple polarizations, each of which represents an independent data stream. The method converts the polarization-multiplexed optical signal to a corresponding polarization-multiplexed electrical signal. The method determines an inverse transformation matrix that meets an independent component analysis (ICA) criterion. The method applies the inverse transformation matrix to the polarization-multiplexed electrical signal, which produces a polarization-demultiplexed electrical signal. The method phase estimates the polarization-demultiplexed electrical signal to recover the data stream.10-20-2011
20100284687All Optical 1+1 Protection Unit Using Sub-Carrier Modulation Protocol - An interface between a network component and an optical fiber section communicates with a remote interface and a remote network component at an opposite end of the optical fiber section through over-modulation of optical signals sent between the interfaces and network components. The over-modulation is at frequencies much lower than the ordinary modulation of the optical signals. The over-modulation allows communication between the interfaces for performing management, testing and maintenance operations and permits superior detection of faults in the optical fiber section.11-11-2010
20100284686PRECURSOR ISI CANCELLATION USING ADAPTATION OF NEGATIVE GAIN LINEAR EQUALIZER - An apparatus including a first circuit and a second circuit. The first circuit may be configured to generate an equalized signal in response to an input signal and an equalizer parameter signal. The equalizer parameter signal generally causes a cancellation of pre-cursor inter-symbol interference from a plurality of symbols in the input signal. The second circuit may be configured to generate (i) the equalizer parameter signal, (ii) a control signal and (iii) a data output signal in response to the equalized signal. The control signal generally causes an adjustment of the equalizer parameter signal. The adjustment of the equalizer parameter signal generally causes a decrease in the pre-cursor inter-symbol interference from the symbols.11-11-2010
20100329666THERMAL CHIRP COMPENSATION IN A CHIRP MANAGED LASER - Thermal chirp compensation in a chirp managed laser. In one example embodiment, a method for thermal chirp compensation in a chirp managed laser (CML) includes several acts. First, a first bias condition and temperature is selected. Next, a first thermal chirp compensation signal is generated. Then, the laser is driven by biasing a first input drive signal with the first thermal chirp compensation signal. Next, a second bias condition and temperature is selected. Then, a second thermal chirp compensation signal is generated. Finally, the laser is driven by biasing a second input drive signal with the second thermal chirp compensation signal.12-30-2010
20100067899Standby restoration signaling for optical networks - Systems and methods are described that provide a distributed restoration signaling protocol for shared mesh restoration with standbys for transparent optical networks.03-18-2010
20090245782NETWORK CONNECTION DEVICE AND SIGNAL PROCESSING METHOD IN THE NETWORK CONNECTION DEVICE - A network connection device for performing a process of transmitting and receiving a SONET/SDH frame includes a first protocol processor which processes a first network management protocol; a second protocol processor which processes a second network management protocol; a frame header extractor which extracts a header from the received SONET/SDH frame; and a protocol identifier which identifies a network management protocol based on the extracted frame header. The network connection device selects one of a control signal outputted from the first protocol processor and a control signal outputted from the second protocol processor based on a result of the identification, and outputs the control signal.10-01-2009
20110097076METHOD AND DEVICE FOR SENDING UPLINK BURST DATA IN PASSIVE OPTICAL NETWORK SYSTEM - A method for sending uplink burst data in a passive optical network (PON) system includes: sending a synchronization pattern of the uplink burst data, the synchronization pattern being of a length, which is an integer multiple of 66 bits, and being formed by connection of 66-bit unit gene blocks; sending a burst delimiter (BD) of the uplink burst data; sending a forward error correction (FEC)-protected data in the uplink burst data; and sending an end of burst (EOB) delimiter of the uplink burst data. The technical solutions in the embodiments allow the use of a less complex equalizer at the reception end of a high-speed PON system.04-28-2011
20110097075NONLINEAR DISTORTION DETECTING CIRCUIT, OPTICAL RECEIVER, OPTICAL TRANSMISSION SYSTEM, AND METHOD FOR DETECTING NONLINEAR DISTORTION - An apparatus includes a first estimator that estimates a signal quality based on an error correction number of an electrical signal obtained by photoelectrically converting a received optical signal; a second estimator that estimates a signal quality from which the influence of nonlinear effects is removed based on signals upstream and downstream of an identification calculator identifying the electrical signal; and a calculator that calculates the difference between the signal qualities estimated by the first and second estimators to calculate the amount of nonlinear effects.04-28-2011
20120008937Power Saving in Passive Optical Networks Using Dynamic Data Rate Scaling - An Optical Network Unit (ONU) in a Passive Optical Network (PON), the ONU comprising: a receiver module configured to receive a first rate selection signal from an optical line terminal (OLT) that indicates a reduced rate mode, and a component comprised within the receiver module, the component configured to transition from a normal operation mode to the reduced rate mode in response to the receiver module receiving the first rate selection signal, wherein operating in the normal operation mode comprises receiving a downstream signal from the OLT at a nominal data rate, and wherein operating in the reduced rate mode comprises receiving the downstream signal from the OLT at a reduced data rate that is less than the nominal data rate but greater than zero.01-12-2012
20110103791Method and System for Monitoring Optical Dispersion in an Optical Signal - A method is provided for dispersion compensation of an optical signal communicated in an optical network. The method may include receiving an optical signal comprising a plurality of channels. The method may further include filtering at least one channel from the plurality of channels. The method may also include analyzing the at least one channel of the plurality of channels to measure optical dispersion in the at least one channel. The method may additionally include compensating for optical dispersion based on the measured dispersion.05-05-2011
20110103790Method and System for Compensating for Optical Impairment in an Optical Signal - Methods and systems are provided for compensating impairment of a signal in an optical network. A method may include: (i) recording, for each node of a plurality nodes of the network, traffic management information specific to such node; (ii) communicating, by each node, its associated traffic management information to one or more other nodes; (iii) receiving, at a particular node of the plurality of nodes, the traffic management information communicated from the one or more nodes; (iv) determining, by the particular node, digital signal processor tap coefficients for a digital coherent receiver integral to the particular node based on at least a portion of the traffic management information; and (v) compensating, by the digital coherent receiver, optical impairment of the optical signal based on at least the determined digital signal processor tap coefficients and processing of the optical signal by a digital signal processor integral to the digital coherent receiver.05-05-2011
20120315030METHOD AND SYSTEM FOR REDUCING TRAFFIC DISTURBANCE IN A COMMUNICATION NETWORK CAUSED BY INTERMITTENT FAILURE - A method may include: (i) in response to clearing of a fault on a working path of a protection switching group to which a first network element is interfaced: (a) transitioning, by the first network element, its state to a first state in which a protection path of the protection switching group is active; and (b) initiating, by the first network element, a wait to restore timer, the wait to restore timer having a duration such that upon expiration of the timer, the first network element is configured to switch the working path to active; and (ii) in response to receiving a message from a second network element interfaced to the protection switching group indicating that a failure has occurred on the working path: (a) maintaining, by the first network element, its state in the first state; and (b) continuing, by the first network element, the wait to restore timer.12-13-2012
20120163794LEVEL TRANSITION DETERMINATION CIRCUIT AND METHOD FOR USING THE SAME - A level transition determination circuit includes a multi-phase clock generator, an oversampling unit, and a state detection circuit. The multi-phase clock generator is used for receiving an input clock signal and generating S×N clock signals, in which S and N are integers. Each clock signal is synchronized to the input clock signal and has a different delay time. The oversampling unit is used for performing N-times oversampling on M bit periods of the serial input data according to the clock signals, so as to generate M×N sampled values in parallel during the M bit periods. The state detection circuit is used for receiving (M×N)+1 sampled values and generating N detection signals by detecting level transitions between adjacent sampled values of the (M×N)+1 sampled values and the level transition results.06-28-2012
20120224845ADMINISTRATIVE BOUNDARIES IN SINGLE OR MULTIPLE DOMAIN OPTICAL NETWORKS - The present disclosure provides systems and methods for administrative boundaries in a single domain optical network such as emulation of an External network-network interface (ENNI) using an Internal-Network to Network Interface (INNI). For example, in a single monolithic domain, a network and associated network elements may discover network elements, build topology, compute paths, establish new calls, etc. A user may identify/mark specific links as emulated “ENNI” links with the specific links actually being INNI links. As a call traverses this emulated link, a new call is initiated (much in the same way a new call segment would be created for a call). Signaling proceeds as normal. When the call set-up is fully complete, instead of a single call segment, many call segments exists. Advantageously, this allows use of INNI control plane features while allowing a network operator to future-proof their network by installing call segments at future boundary points.09-06-2012
20120177361COMMUNICATION METHOD, OPTICAL COMMUNICATION SYSTEM, STATION-SIDE OPTICAL-LINE TERMINAL APPARATUS, AND USER-SIDE OPTICAL-LINE TERMINAL APPARATUS - An ONU includes the optical transceiver capable of an operation in a power-saving mode in which power consumption is reduced by stopping transmission while continuing reception, and a control device that controls to tentatively validate transmission of the optical transceiver and outputs a response signal when a control signal is received from an OLT during an operation in a power-saving state. Moreover, the OLT includes the control device that allocates a transmission bandwidth to the ONU even while the optical transceiver of the ONU operates in a power-saving mode and stops transmission and determines whether a communication failure occurs or the ONU is in operation in a power-saving mode based on the response signal received by a transceiver of the OLT.07-12-2012
20120177360TRANSMISSION APPARATUS AND REPORTING METHOD FOR REPORTING FAULT - A transmission apparatus includes a processor that is operative to terminate a first line performing a communication using a digital wrapper, to terminate a signal on a second line performing a communication using Gigabit Ethernet, to apply a transparent transcoding process to a terminated signal and the signal received from the second line and to output these signals; and wherein when a fault occurs in a communication performed through the first line and when there is no response for a predetermined time period after an auto negotiation restart signal is reported to an opposite apparatus on a second line side, to report information indicating an occurrence of the fault to the opposite apparatus by using a signal of a MAC (Media Access Control) frame format.07-12-2012
20100272430SYSTEM AND METHOD FOR CONSECUTIVE IDENTICAL DIGIT REDUCTION - In a data transmission network, such as a passive optical network, the consecutive identical digit (CID) handling requirements may be reduced by providing a CID monitoring module at the transmitter end that monitors the number of CIDs in a transmission stream. Where the CID number exceeds a threshold, an error generation module induces an error in the transmission stream to reduce the CID below the threshold. The modified transmission stream may then be transmitted to a receiver, allowing clock recovery be performed with improved stability at the receiver. Once clock recovery is achieved, the receiver can then process the transmission stream to correct the errors induced at the transmitter end.10-28-2010
20120230671COMMUNICATION DATA TRANSMISSION EQUIPMENT, A COMMUNICATION DATA TRANSMISSION SYSTEM, A COMMUNICATION DATA TRANSMISSION METHOD AND A COMMUNICATION DATA TRANSMISSION PROGRAM - Even in a network system including a transmission line of which dominant cause of delay is a transmission line delay, controlling communication speed of the network system as a whole efficiently and suppressing the delay is made possible.09-13-2012
20120321295SIGNAL PATH CONTROL DEVICE - A device for signal path control includes a first input terminal and a first output terminal for coupling the signal path control device to a communication network. The device also includes a second input terminal and a second output terminal for coupling the signal path control device to a network device, and a relay input terminal coupleable to a relay output terminal of the network device. In a first operation mode, the device directs signals received via the first input terminal to the second output terminal, which is coupleable to an input terminal of the network device. In a second operation mode, the device directs signals received via the first input terminal to the first output terminal. The device switches between the operation modes in response to a trigger signal received via the relay input terminal.12-20-2012
20120087649Method and system for instructing enabling/disabling forward error correction coding function - The present invention discloses a method for instructing enabling/disabling Forward Error Correction (FEC) function. The method comprises: presetting an instruction identifier of an FEC status; transmitting an instruction identifier of an FEC status of an Optical Network Unit (ONU) and the Identity (ID) of the ONU by an Optical Line Terminal (OLT), wherein the instruction identifier of the FEC status of the ONU is corresponding to the ID of the ONU; and enabling or disabling its own FEC function by the ONU according to the received instruction identifier corresponding to its own ID. The present invention also discloses a system for instructing enabling/disabling FEC function, which comprises an OLT and an ONU. The method and system of the present invention can solve the problem that the ONU cannot determine the instruction from the OLT due to an error code.04-12-2012
20120087648METHOD AND SYSTEM FOR PROTECTION SWITCHING - A method is provided for protection switching in an optical network. The method may include communicating a switch request for initiation of protection switching in response to a determination that at least a minimum frequency of interrupts indicating failure of an optical signal has occurred over a first period. The method may also include communicating a switch request for cessation of protection switching in response to a determination that no more than a maximum frequency of interrupts indicating failure of an optical signal has occurred over a second period.04-12-2012
20130016964METHOD AND SYSTEM FOR FAULT RECOVERY IN AN OPTICAL NETWORKAANM Mu; RuomeiAACI East BrunswickAAST NJAACO USAAGP Mu; Ruomei East Brunswick NJ USAANM Golovchenko; Ekaterina A.AACI Colts NeckAAST NJAACO USAAGP Golovchenko; Ekaterina A. Colts Neck NJ USAANM Kerfoot, III; Frank W.AACI Red BandAAST NJAACO USAAGP Kerfoot, III; Frank W. Red Band NJ US - A method of managing fault recovery in a trunk-branched OADM network may include determining that an optical power level over data channels of a first communications link between a first and a second terminal of the branched optical network exceeds an optical power limit. The method may further include increasing optical power sent over spare channels of the first communications link to a first level at which the optical power level over the data channels decreases to a second level below the optical power limit.01-17-2013
20080226287Method and Apparatus for Restoration of Operating Conditions of an Optical Ring Network Comprising a Plurality of Optical Amplifiers After a Break or Other Fault in the Ring Network - A method and apparatus for restoration of operating conditions of a WDM optical ring network comprising a plurality of amplifiers linked together in a ring after a break or fault has occurred in the network. The method comprises in response to repair of the break or other fault, increasing output power or/and pump power of an amplifier in the network such that the output power or/and pump power increases substantially in accordance with a ramp function.09-18-2008
20110311216OPTICAL SIGNAL LEVEL ADJUSTMENT SYSTEM, INFORMATION ANALYSIS/CONTROL SIGNAL GENERATION APPARATUS IN THE SAME SYSTEM, AND INFORMATION ANALYSIS/CONTROL SIGNAL GENERATION METHOD - The present invention enables to prevent transmission characteristics from deteriorating due to the nonlinear effect in the transmission path caused by an increase in the channel power when a cable disconnection occurs. An optical signal level adjustment method comprises the steps of: obtaining, based on one or more optical signal disconnections which are detected per wavelength block and each of which is detected by a signal disconnection detection section included in each of terminal station devices, a location at which the optical signal disconnection has occurred, a combination of a terminal station device and a wavelength block, and a dummy light adjustment amount, said combination being required to be subjected to adjustment of transmission dummy light, said combination and said dummy light adjustment amount corresponding to the location; and transmitting, to the terminal station device which is required to be subjected to adjustment of the transmission dummy light, a control signal for adjusting the intensity of the dummy light in the obtained wavelength block by the dummy light adjustment amount.12-22-2011
20130202285SYSTEM AND METHOD FOR TRANSPORTING ELECTRIC POWER AND PROVIDING OPTICAL FIBER COMMUNICATIONS UNDER SEA WATER - A network for transporting communication and power. The network comprises terminal stations branching units and subsea nodes connected to a branching unit, wherein at least one connection path between a terminal station and a first branching unit and between the first branching unit and a first subsea node is provided by means of optical fiber, and wherein said first subsea node is adapted to receive a plurality of wavelengths and provide at least one wavelength at an output thereof. The network comprises a first power supply connected to a first cable head of the trunk cable and at least a second power supply connected to a second cable head of the trunk cable. The first power supply and the at least second power supply, supply at least a minimum amount of electric current in the network either individually or in combination, under normal or faulty conditions.08-08-2013
20130209086CLEARING A FAULT CONDITION OVER A FIBRE CHANNEL PATH - A method for clearing a fault condition at a target device is disclosed herein. In selected embodiments, such a method includes detecting a fault condition at a target device and receiving N instructions before the fault condition is cleared, where the N instructions are unexecutable due to the fault condition. N fault condition indicators are transmitted in response to the N instructions. Clearing of the fault condition is detected when the fault condition no longer exists. Acknowledgments corresponding to the fault condition indicators are received, where each acknowledgment indicates that one of the fault condition indicators has been received. A fault clear indicator is transmitted only after both all N fault condition indicators have been received and clearing of the fault condition has been detected. A corresponding system and computer program product are also disclosed herein.08-15-2013

Patent applications in class FAULT RECOVERY

Patent applications in all subclasses FAULT RECOVERY