Abstract: Systems and methods for conveying wavelength tuning information from a pluggable optical transceiver to a host device determining the wavelength tuning information of the pluggable optical transceiver operating in the host device; appending the wavelength tuning information as part of existing data communicated between the pluggable optical transceiver and the host device; and providing the existing data with the wavelength tuning information incorporated therewith to the host device.

Abstract: A wavelength division multiplexing system and method featuring a wavelength monitor that is configured to receive a portion of a combined signal of wavelength division multiplexing channels and determine the wavelengths of each channel or the guardband between each channel in the combined signal. The wavelength monitor determines if there is excess laser drift for each channel in the combined signal. If excess laser drift is determined, feedback is sent to the transmitter for the signal with excess laser drift and the signal is adjusted to produce a target wavelength. The wavelength monitor may utilize optical intradyning in order to monitor the wavelengths of each channel in the combined signal.

Abstract: In some aspects, an example method may include receiving, at a receiver of a first optoelectronic module, a loss of signal indicator from a second optoelectronic module that is remote from the first optoelectronic module. The method may include iteratively cycling through transmission of optical signals on a plurality of wavelength channels to the second optoelectronic module until the loss of signal indicator terminates in response to receiving the loss of signal indicator. The method may include continuing to transmit the optical signal on a particular one of the plurality of wavelength channels in response to the loss of signal indicator terminating while transmitting an optical signal on the particular one of the plurality of wavelength channels.

Abstract: A method of monitoring at least one optical wavelength component of a WDM optical signal being routed through a wavelength selective switch (WSS) includes directing an optical wavelength component from a given input port of the WSS to a selected output port with a selected amount of attenuation. A rejected portion of the optical wavelength component giving rise to the selected amount of attenuation is directed to an optical monitor associated with another output port of the WSS. A power level of the optical wavelength component is determined by pre-calibrating a proportionality between the power level of the wavelength component and the power level of the rejected portion that is directed to the optical monitor.

Abstract: A communications controller, and corresponding method therein, for wavelength control of a first and second channel. The first and second channels are bidirectional and adjacent to one another in a single fiber in a Dense Wavelength Division Multiplexing (DWDM) based system.

Abstract: A multiport optical switch (such as an N×1 switch) is used to controllably select a specific incoming optical signal that is to be processed by an associated optical channel monitor (OCM). The OCM includes a tunable optical filter and photodetector arrangement, and is configured to measure the optical spectrum of the incoming optical signal and extract information associated with the various optical channels (wavelengths) forming the incoming optical signal (i.e., power, wavelength, OSNR and the like for each channel). The OCM also includes a signal processing component that generates a pair of output control signals, a first signal to control the wavelength scanning process of the tunable optical filter and a second signal to control the setting of the multiport optical switch.

Abstract: The present invention as disclosed and described herein, in one aspect thereof, comprises a method for multiple access communications over a communications link involves receiving a plurality of data streams from a plurality of data sources. The plurality of data streams are grouped into a plurality of groups. Orthogonal frequency division multiplexing (OFDM) processing is applied to each of the plurality of groups. Each of the plurality of groups uses a same combination of frequency and time slot combinations in the OFDM processing. A different orthogonal function is applied to each of the OFDM processed groups to uniquely identify each of the OFDM processed group from each other and the orthogonal function processed groups are transmitted over the communications link.

Abstract: A laser module includes a light source device having a first amplifier that outputs first output light, and a second amplifier that outputs second output light, a first drive circuit that supplies the first amplifier with a first drive current, a second drive circuit that supplies the second amplifier with a second drive current. A dither signal is superimposed on one of two drive currents to respectively grasp the characteristics of the two amplifiers.

Abstract: Device and method for optically switching a plurality of optical input signals include: receiving the plurality of optical input signals, wherein one or more of the optical input signals represent multiple channels at different channel frequencies; collimating the received plurality of optical input signals; removing noise between the channels by a comb filter; dispersing the collimated optical signals so that signals of different wavelength are separated by different angles; focusing the optical signals separated by different angles on a light switch device having a plurality of micromirrors; and controlling the light switch by a control signal to direct one or more of the optical signals separated by different angles to one or more output fibers for multicasting of the optical input signals.

Abstract: A method that may include receiving a block of signals from a certain wavelength division multiplex (WDM) channel out of a set of WDM channels; analyzing at least a first sub-block of signals of the block of signals to provide analysis results indicative of interferences that affect the first sub-block of signals and result from transmissions over other WDM channels of the set of WDM channels; and mitigating interferences that affect the block of signals in response to the analysis results.

Abstract: In one embodiment, an optical performance monitor (OPM) is configured to monitor a received optical wavelength-division-multiplexed (WDM) signal generated by modulating spectral lines of an optical frequency comb. The OPM is further configured to mix the received optical WDM signal with light of another optical frequency comb having a slightly different tooth spacing to generate a set of beat signals at frequencies representing frequency differences between the spectral lines (such as, at the carrier frequencies) of the optical WDM signal and the spectral lines of said another optical frequency comb. The OPM can further be configured to measure one or more parameters of the received optical WDM signal based on the characteristics of the generated beat signals and provide the resulting OPM data to a system controller for maintaining favorable signal-transport conditions within the system.

Abstract: A pre-emphasis control method includes calculating an average value of transmission characteristics based on transmission characteristics of a plurality of light beams received by a receiver, and determining that, among signals of the plurality of light beams, a wavelength with a deviation from the average value is a wavelength at which control is to be performed, determining that the wavelength at which control is to be performed and a wavelength adjacent thereto are a group of wavelengths at which control is to be performed, obtaining an average of transmission characteristics of the group of wavelengths at which control is to be performed, and based on a difference between averaged transmission characteristics and respective transmission characteristics of the group of wavelengths at which control is to be performed, changing a light intensity output from each transmitter that transmits a group of wavelengths at which control is to be performed.

Abstract: A method of monitoring a WDM optical signal is provided. The method includes: receiving a WDM optical signal having a plurality of channels; detecting the optical signal after filtering the WDM optical signal with a tunable filter; and reconfiguring at least the center wavelength and bandwidth of the tunable filter optical transfer function to determine a signal performance parameter of the WDM optical signal.

Abstract: An optical transmission system includes: a first optical transmission device configured to perform bidirectional optical transmission with a second optical transmission device via an optical transmission line, wherein the first optical transmission device includes a transmitted light power adjusting section configured to transmit, to the second optical transmission device, a first light power which is set based on a measurement result, the second transmission device measuring a fluctuating light power transmitted from the first transmission device and informing the first transmission device of the measurement result.

Abstract: A system, a device, and a method include a network interface device that measures optical power of a passive optical device; generates optical power data, and stores the optical power data. The system, the device, and the method, also includes generating alarms based on the optical power data and communication with remote network interface devices via the passive optical device.

Abstract: In general, the 1G-EPON standard specifies its upstream waveband broadly to allow for low cost lasers to be used to transmit upstream. Often, however, the lasers actually used by many 1G-ONUs to transmit upstream only occupy a narrow waveband that does not overlap with the upstream waveband specified by the 10G-EPON standard. The present disclosure is directed to systems and methods that exploit this fact to efficiently provide for the coexistence of 10G-EPON and 1G-EPON over the same set of optical fibers in the upstream direction.

Abstract: A WDM signal light monitoring device includes a first monitor for monitoring input-side WDM main signal light and output-side WDM main signal light for each wavelength; and a second monitor for monitoring the first monitor by comparing a monitoring result received from an upstream WDM transmission device with a monitoring result of the first monitor, wherein the monitoring result of the first monitor is transmitted to a downstream WDM transmission device in the system.

Abstract: An optical transmission device includes: a reception unit configured to receive a plurality of light beams and wavelength allocation information of optical signals included in each of the light beams; a demultiplexing unit configured to demultiplex the plurality of light beams received; a plurality of switches configured to switch between transmitting or blocking with respect to the demultiplexed plurality of light beams; a multiplexing unit configured to multiplex light beams transmitted from the plurality of switches; a monitoring unit configured to monitor an intensity of the multiplexed light beams; and a controller configured to, based on the wavelength allocation information, obtain a combination of the light beams not including the optical signals having overlapping wavelengths, and control the plurality of switches in accordance with the combination.

Abstract: An optical network (1) comprising an optical network element (10) comprising a first optical transmitter (14), a first controller (16), a first optical receiver and a second optical receiver and a second optical network element (12). There is provided a transmission path (30) between said first optical network element and said second optical network element. Said first optical transmitter is arranged to generate and transmit a first optical signal. Said first controller is arranged to control said first optical transmitter to generate and transmit said first optical signal at a wavelength selected from a predetermined plurality of wavelengths. Said first optical receiver is arranged to detect a backscatter portion of said first optical signal returned to said first optical network element along said transmission path by distributing scattering.

Abstract: An apparatus determines, in response to demands for traffic between nodes in a network transmitting wavelength-multiplexed optical-signals, routes each providing connection between nodes, and estimates, for each link, communication-channels to be established, based on a wavelength-constraint condition that the number of communication-channels to be established be not greater than a first upper-limit for available optical-signal wavelengths. The apparatus assigns wavelengths to the communication-channels, based on a system-constraint condition that the number of optical-signals having an identical wavelength and redundantly usable be not greater than a second upper-limit for available transmission-systems. The apparatus determines a target-number of wavelengths for reducing a required number of transmission-systems.

Abstract: A test apparatus and method for testing passive optical networks is provided. The test apparatus includes an optical circuit having an optical coupler for splitting off a portion of optical traffic. During testing of a passive optical network, the optical circuit is coupled into an optical path of the passive optical network. A bit stream corresponding to an activating procedure is captured and analyzed to extract identification information of the module that sent the bit stream.

Abstract: Based on the demand information etc., an accommodation designing problem and an assignment problem are solved in a conventional method to design a network. It is confirmed whether or not a restriction on the number of wavelengths for each link is observed. When there are links exceeding the restriction of the number of wavelengths, the number of available wavelengths is subtracted from the first link having the largest number of excess wavelengths and the second link farthest from the first link in the links, and the result is set as a wavelength number limited value, thereby performing a network designing process again.

Abstract: Methods and systems are disclosed including receiving, by circuitry of a node conforming to GMPLS protocol, a signal comprising at least one of an optical signal attribute indicative of parameters of a super-channel, the super-channel including a plurality of optical carriers, each of which having a corresponding one of a plurality of wavelengths and being modulated to carry a corresponding one of a plurality of data streams, the super-channel being provisioned in the optical network as one optical channel, wherein the optical signal attribute is one of: quantity of wavelengths of the super-channel, wavelength center frequency of the super-channel, wavelength modulation of the super-channel, wavelength baudrate of the super-channel, and wavelength FEC type of the super-channel. The node further receiving information indicative of frequency slices in use by the super-channel and calculating, using algorithms conforming to CSPF-TE protocol, a path of a second super-channel.

Abstract: Due to demand for more network bandwidth, a need for multi-user optical network topologies has, and will continue to, increase. A method or corresponding apparatus in embodiments of the present invention provide for an availability determination tool for determining and displaying wavelength and subrate availabilities within a network. Benefits of embodiments of a tool include allowing a user to identify the availability and capacity of any wavelength on any network, via an interactive graphical user interface, such as by using three-dimensional representations. In one embodiment, the disclosed availability determination tool allows users to locate and view any combination of available wavelengths between nodes in an optical network topology, and generate graphical and tabular reports of the availability in order to maintain an efficient and organized method or apparatus for determining and controlling wavelengths in a network.

Abstract: A digital signal processor (DSP) may receive samples of a signal from an analog-to-digital converter (ADC); convert the samples from a time domain to a frequency domain; determine a clock phase error of the samples while in the frequency domain; and provide a voltage corresponding to the clock phase error. The voltage may be provided to reduce timing errors associated with the samples.

Abstract: An optical transmission system includes: a plurality of optical transmission devices each including: an adjustment unit to adjust optical power of channels in the WDM optical signal; and a controller to control the adjustment unit based on an adjustment amount, and a management device including: a converter to convert an evaluation value for evaluating quality of service provided by using the channels in the WDM optical signal into a threshold value of transmission quality to be satisfied by the channels; and a determination unit to calculate the transmission quality of the channels based on monitoring information of the channels in the WDM optical signal adjusted by the adjusting unit of at least one of the plurality of optical transmission devices and to determine the adjustment amount to be set for the optical transmission device so that the calculated transmission quality of the channels satisfy the threshold value.

Abstract: An optical transport network signal (OTM) comprising at least one optical channel is received at a first network equipment. The optical transport network signal (OTM) is processed to extract optical data units (ODUk) for each optical channel (OCh). There is detection for defects during the processing. The optical data units are retransmitted within optical transport units (OTUk) towards a second network equipment. When a defect has been detected, the retransmitting comprises inserting an optical channel transport unit alarm indication signal (OTUk-AIS) in an optical channel transport unit (OTUk) containing optical channel data units (ODUk) that are affected by the detected defect.

Abstract: An apparatus for measuring optical power including a first multiplexer/demultiplexer to split/combine an optical signal including a first wavelength and second wavelength; a second multiplexer/demultiplexer to split/combine an optical signal including the first wavelength and the second wavelength; a first tap photodetector coupled to the first and second multiplexer/demultiplexers and to a first measurement device; and a second tap photodetector coupled to the first and second multiplexer/demultiplexers and to a second measurement device.

Abstract: An optical receiving device includes: an optical amplifier configured to amplify a wavelength multiplexed optical signal; a demultiplexer configured to demultiplex the amplified wavelength multiplexed signal into optical signals of a plurality of wavelengths; optical receivers configured to regenerate the demultiplexed optical signals; error correction units configured to correct a bit error in the regenerated optical signals; and main control unit. The control unit adjusts RXDTV of the optical receiver for receiving optical signals of a given wavelength to the optimal value in the state where the gain of the optical amplifier is lowered from that of a normal operation such that the occurrence of bit errors in the optical signals of the other wavelengths does not exceed the correction capability of the error correction unit.

Abstract: Described herein is an optical channel monitor (1) including one or more input optical ports (3) for receiving an input optical signal (5) including a plurality of optical channels. A first monitoring module (7) is configured to selectively scan a predetermined spectral region of the optical signal including at least one optical channel for low resolution monitoring. A second monitoring module (11) is configured to simultaneously scan a subregion within the predetermined spectral region for high resolution monitoring.

Abstract: A system to provide carrier frequency control in an optical network includes a first network element monitoring performance information and a second network element coupled to the first network element by the optical network. The second network element receives performance information from the first network element using an administration channel bandwidth, and modifies a carrier frequency associated with the second network element based on the performance information such that the carrier frequency is aligned to a center of a signal channel bandwidth. A method of providing carrier frequency control includes transmitting performance information by the first network element to the second network element using an administration channel bandwidth, and modifying the carrier frequency by the second network element based on the performance information such that the carrier frequency is aligned to the center of the signal channel bandwidth.

Abstract: A method for detecting branch fibers is provided, which includes: sending test signals to a plurality of branch fibers, where the test signals are added at ports of the optical splitting module with identification information for identifying branch fibers connected to the ports and receiving a reflection signal added with the identification information of a detected branch fiber, identifying the detected branch fiber corresponding to the reflection signal through detecting the identification information added to the reflection information, and obtaining channel characteristics of the detected branch fiber according to the reflection signal. Further, a system and an apparatus for detecting branch fibers are provided.

Abstract: An optical communication apparatus includes a variable resistor unit, a measurement unit, and a control unit. The variable resistor unit is arranged at a pre-stage of an electrical/optical conversion unit, which converts an electrical signal obtained by converting an input packet to an optical signal having a waveform corresponding to a potential difference between a positive phase component and a negative phase component of the electrical signal by using the potential difference. The variable resistor unit provides a resistor that varies a midpoint of potential of the positive phase component or the negative phase component. The measurement unit measures a ratio of a presence period, which is a period where the input packet is present, to a sum of the presence period and a non-presence period. The control unit controls a value of the resistor provided to the positive phase component or the negative phase component based on the ratio.

Abstract: An optical signal monitor circuit is an optical signal monitor circuit including a PD which directly detects an optical signal and converts the optical signal into a photocurrent, a PD which detects the optical signal and converts the optical signal into a photocurrent, a resistance element which converts these photocurrents into voltages, and an operational amplifier which outputs the voltages generated by the resistance element, wherein the optical signal monitor circuit further includes a switching control circuit which switches a connection between the PDs and the resistance element, and a calculation circuit which acquires the output of the operational amplifier as a digital signal, the switching control circuit controls switching to flow the two photocurrents into the resistance element at individual timings and flow the two photocurrents into the resistance element at the same timing, and the calculation circuit calculates a corrected digital signal by subtracting the obtained digital signal.

Abstract: An optical packet switching apparatus includes an optical packet switching apparatus, an optical transmitting apparatus, and an optical packet receiving apparatus. The optical packet transmitting apparatus includes a packet generator for generating a packet signal by adding the routing information to a received client signal, a BIP adding unit for adding BIP to the generated packet signal, and an electrical-to-optical converter for converting the packet signal, to which the BIP has been added, into an optical packet signal so as to be sent out. The optical packet receiving apparatus includes an electrical-to-optical converter for converting the received optical packet signal into an electrical packet signal, and a BIP comparison unit for detecting the error occurrence in the packet signal, based on the BIP added to the packet signal.

Abstract: A network traffic collecting and monitoring system includes a traffic processing and dispatching module that pre-processes network traffic received from traffic tapping modules. A traffic collecting module receives and consolidates the network traffic and sends the network traffic to higher-layer applications. A controller dynamically configures the traffic processing and dispatching module to achieve optimal measurement accuracy and network coverage.

Abstract: An integrated mobile communication repeater monitoring device, and method and system for mobile communication relay and information provision, is provided. Signals received from communication networks are divided into signals of mobile communication channels and signals of data channels, mobile communication services are provided to on the basis of the signals of the mobile communication channels, and data is displayed on the basis of the signals of the data channels.

Abstract: A laser system includes an array of lasers that emit light at a number of different, fixed wavelengths. A group of optical transport systems connect to the laser system. Each of the optical transport systems is configured to modulate data signals onto the light from the laser system to create optical signals and transmit the optical signals on one or more optical fibers.

Abstract: In an optical communication device, a light source is capable of varying the wavelength of light to be output. An optical multiplexer multiplexes light output from the light source with signal light received from a transmission path. To an optical medium, light output from the optical multiplexer is input. A monitor monitors light having a predetermined wavelength output from the optical medium. A wavelength number measuring unit measures the number of wavelengths of signal light transmitted through the transmission path based on the result of monitoring by the monitor.

Abstract: There is provided a method of determining transmission quality of a path in an optical communication network system obtained by connecting a plurality of networks, the method including: acquiring a value representing transmission performance corresponding to a network condition of each of spans in the path in the optical communication network system; and determining the transmission quality of the path on the basis of the acquired value representing transmission performance corresponding to the network condition of each of spans.

Abstract: An optical amplifier that uses software-defined optical networking (SDON) technology, with a centralized controller and flexible physical hardware (the adaptive amplifier here) to optimize the power distribution among different WDM channels in the amplifier. It considers the detailed information for each channel through the information from centralized controller. It is suitable for both single line rate and mixed line rate system, and is suitable for a wavelength division multiplexing WDM system with the same signal type or different signal types.

Abstract: Disclosed is an optical line terminal for monitoring and controlling upstream and downstream optical signals, and more particularly, to an optical line terminal for monitoring and controlling upstream and downstream optical signals, which adds different low frequency monitoring signals to upstream and downstream wavelength division multiplexing optical signals in a bidirectional wavelength division multiplexing (WDM) optical network and senses and detects low frequency components of upstream and downstream optical signals to unite, monitor, and control optical outputs and wavelengths of the upstream and downstream wavelength division multiplexing optical signals into a single system.

Abstract: A path computation client (PCC) can request a path computation element (PCE) to compute a path across a wavelength switched optical network. PCC sends a request which identifies end nodes. The end nodes can support a plurality of possible values of a transmission parameter, such as modulation format or Forward Error Correction (FEC) type. The PCE computes a path between the end nodes and sends a reply to the PCC. The reply identifies the path between the end nodes and identifies a selected value of the transmission parameter for the computed path. The reply can comprise a spectrum assignment for the path. The reply can be a PCE Communication Protocol (PCEP) Reply message.

Abstract: An optical transmitter may include an optical source to provide a first optical signal having a varying frequency; an optical circuit to receive a portion of the first optical signal and provide a second optical signal corresponding to a change in frequency of the first optical signal; a photodetector to receive the first optical signal and provide an electrical signal that is indicative of the change in frequency of the first optical signal; an integrator to receive the electrical signal and provide an inverted electrical signal; and a controller to process the inverted electrical signal and provide a current, associated with the inverted electrical signal, to the optical source. The optical source may reduce the phase noise associated with the first optical signal based on the current.

Abstract: An optical channel monitor includes a demultiplexer, a plurality of paths and a processing section. The demultiplexer demultiplexes an input optical signal, which is wavelength-multiplexed, for respective multiplexed wavelengths to generate a plurality of optical signals. The plurality of paths respectively generate a plurality of digital signals indicating optical powers of the plurality of optical signals. The processing section inputs the plurality of digital signals to calculate correction values of the optical powers, which correspond to characteristics of the demultiplexer. The demultiplexer includes a filter having FMHM (Full With at Half Maximum) within a predetermined range. The predetermined range is set based on a pass center wavelength accuracy of the filter and an oscillation wavelength accuracy of a transponder which generates the input optical signal.

Abstract: A system and method is disclosed that allows for the monitoring, analyzing and reporting on performance, availability and quality of optical network paths. The correlation of PM parameter metrics to client connections, coupled with threshold-based alarm generation provides a proactive and predictive management, reporting and analyzing of the health and effectiveness of individual path connections to alert Operational Support (OS) staff and/or customers to signal degradation and impending Network Element (NE) failures. The system and method performs in real-time processing intervals required for alarm surveillance in a telecommunications network.

Abstract: In accordance with the present disclosure, disadvantages and problems associated with transmitting high capacity (e.g., 400 G) optical signals may be reduced. In accordance with an embodiment of the present disclosure a method for regenerating an optical signal comprises receiving an optical signal at a network element and measuring a performance characteristic of the optical signal. The method further comprises determining that the optical signal needs regeneration based on the performance characteristic of the optical signal. The method additionally comprises performing signal regeneration of the optical signal based on the determination that the optical signal needs regeneration.

Abstract: Optical service channel (OSC) systems and methods over high loss links are described utilizing redundant telemetry channels. A first telemetry channel provides a low bandwidth communication channel used when Raman amplification is unavailable on a high loss link for supporting a subset of operations, administration, maintenance, and provisioning (OAM&P) communication. A second telemetry channel provides a high bandwidth communication channel for when Raman amplification is available to support full OAM&P communication. The first and second telemetry operate cooperatively ensuring nodal OAM&P communication over high loss links (e.g., 50 dB) regardless of operational status of Raman amplification.

Abstract: To, even when a transmission wavelength varies in each ONU and an optical amplifier gain depends on the wavelength in an OLT equipped with an optical amplifier, prevent the optical amplifier gain from varying in every ONU and thus prevent deterioration of a dynamic range. The OLT estimates a transmission wavelength of each ONU at the time of ONU registration, and retains a correspondence between an ONU identifier and the transmission wavelength. Moreover, for every burst, an injection current to the optical amplifier is adjusted based on a wavelength and optical amplifier characteristic database.

Abstract: A transmission apparatus includes: an amplifier controller configured to determine a target value for an average optical input power of a transmitting amplifier in a transmitting-side apparatus, based on an index based on a quality of transmission from an output of the transmitting amplifier to an output of a receiving amplifier in a receiving-side apparatus; and a pre-emphasis controller configured to determine amounts of adjustment of transmission optical powers for respective wavelengths, based on the target value and per-wavelength reception optical powers at the output of the receiving amplifier.