Abstract: Systems and methods for modeling non-visible optical sources in a spectrum controller for control thereof include receiving channel routing information and signal characteristics for the non-visible channels separately from visible channels, wherein the visible channels are formed by optical transceivers communicatively coupled to the spectrum controller and the non-visible channels are formed by optical transceivers without communication to the spectrum controller; utilizing a combination of the channel routing information and signal characteristics for both the visible channels and the non-visible channels as input to the spectrum controller; performing control of optical spectrum based on the input; and providing output adjustments based on the control.

Abstract: It is difficult in an optical network to achieve fault recovery in case of multiple failures without decreasing the usage efficiency of the optical network; therefore, an optical communication system according to an exemplary aspect of the present invention includes an optical network management device including an optical path setting means for setting, to a physical route differing from each other, a backup path corresponding to each of a plurality of active paths on an identical physical route, and a failure-case optical path setting means for setting a failure-case backup path with a compressed band of the backup path, to a physical route without a failure in a case where failures arising on more than one physical route among the physical routes; and an optical node device including an optical transceiver means for transmitting and receiving optical signals using failure-case backup path information resulting from setting by the failure-case optical path setting means.

Abstract: A light emitting device with a dimming visible light communication function and an interaction device applying for visible light are provided. The light emitting device with the dimming visible light communication function comprises a luminance adjusting unit, a control circuit and a light emitting device. The luminance adjusting unit outputs a luminance adjusting signal according to luminance adjusted by a user. The control circuit coupled to the luminance adjusting unit outputs a pulse width modulation (PWM) signal according to the luminance adjusting signal. The light emitting device outputs visible light, receives the PWM signal, and is turned on or off according to states of a logic high voltage and a logic low voltage of the PWM signal. In an idle mode, the PWM signal operates at a first frequency. In a light communication mode, an operating frequency of the PWM signal is changed according to transmitted data.

Abstract: A method, apparatus and system estimating channel power, and monitoring a frequency spectrum characteristic. A method for estimating channel power includes extracting frequency spectrum information from a received signal, so as to obtain a frequency spectrum of the received signal, estimating power of a central channel in the frequency spectra according to a power value of a flat area of the central channel, and estimating power of a neighboring channel in the frequency spectra according to a power value of a flat area of the neighboring channel. With the embodiments of the present disclosure, the power of the central channel and the power of the neighboring channel may be estimated by using only frequency spectrum information obtained by a single optical receiver, so as to quantitatively evaluate influence of a power imbalance effect, thereby ensuring precision of the power estimation, and reducing effects of nonideal factors on the estimated values.

Abstract: A Light Emitting Diode (LED) based illumination device authenticates a mobile electronics device on a lighting communications network. The mobile electronic device may request a communications link on the lighting communications network and detect modulated illumination light emitted from the LED based illumination device. The modulated light may include an optical code. The mobile electronic device may determine the optical code from the modulated illumination light and communicate an indication of the optical code to the LED based illumination device. The LED based illumination device may determine if the indication of the optical code is correct and provide, in response, a communication link to the mobile electronics device on the lighting communications network.

Abstract: Disclosed are methods for monitoring and measuring Optical Signal-To-Noise Ratios in optical communications systems. One exemplary method involves intentionally inserting zero power symbols into an optical signal stream such that those periods of time in which only zero power symbols are transmitted may be detected and compared with periods of time in which signals modulated with information including both signal and noise are detected such that the OSNR may be determined.

Abstract: An optical communication system provides coherent optical transmission for metro applications. Relative to conventional solutions, the optical communication system can be implemented with reduced cost and can operate with reduced power consumption, while maintaining high data rate performance (e.g., 100 G). Furthermore, a programmable transceiver enables compatibility with a range of different types of optical networks having varying performance and power tradeoffs. In one embodiment, the optical communication system uses 100 Gb/s dual-polarization 16-point quadrature amplitude modulation (DP-16QAM) with non-linear pre-compensation of Indium Phosphide (InP) optics for low power consumption.

Abstract: Optical signal to noise ratio within a band of interest (in-band OSNR) is calculated by using a reference signal for noise estimation. In-band noise at a node along the optical communication path is estimated by subtracting the reference signal contribution from the received in-band signal energy. Contribution from the reference signal is calculated using an effective transfer function of the optical communication path using either a direct method in which measurements are made a priori on an equivalent optical system or an indirect method in which the effective transfer function is calculated using computerized simulations. The selection of which method to use may be based on the desired resolution bandwidth for the estimation of transfer function.

Abstract: [Objective] To make it possible to effectively relay remaining signals even when any input failure occurs on a propagation path.

Abstract: A method for using an external lamp onboard a vehicle is provided. The method receives, at a transceiver positioned inside a sealed casing of the external lamp, a wireless communication signal and a wireless power signal; and operates the external lamp using the wireless communication signal and the wireless power signal.

Abstract: Techniques for guard band utilization for wireless data communication are described. In at least some embodiments, guard bands can be leveraged to transmit wireless broadband data and/or other forms of wireless data. According to one or more embodiments, signal activity in a wireless channel that is adjacent to a guard band is monitored, e.g., while the guard band is being utilized for wireless data communication. In at least some implementations, if the signal activity exceeds a signal activity threshold, usage of the guard band channel can be adjusted to mitigate interference with signal activity in an adjacent channel.

Abstract: The present invention concerns the compounds of formula the N-oxide forms, the pharmaceutically acceptable addition salts and the stereochemically isomeric forms thereof, wherein Z represents NH; Y represents —C3-9alkyl-, —C1-5alkyl-NR13—C1-5alkyl-, —C1-5alkyl-NR14—CO—C1-5alkyl-, —C1-2alkyl-NR21—H2—CO—NH—C1-3alkyl- or —C1-2alkyl-NR23—CO—CR16R17—NH—; X1 represents O or —O—C1-2alkyl-; X2 represents a direct bond, C1-2alkyl, —CO—C1-2alkyl or NR12—C1-2alkyl; R1 represents hydrogen or halo; R2 represents halo, acetylene or Het1 R3 represents hydrogen or cyano; R4 represents Ar4—C1-4alkyloxy-, C1-4alkyloxy- or C1-4alkyloxy substituted with one or where possible two or more substituents selected from Het2, NR7R8, hydroxy and C1-4alkyloxy—C1-4alkyloxy-; R7 represents hydrogen or C1-4alkyl; R8 represents C1-4alkyl substituted with NR25R26 or C1-4alkylsulfonyl; R12 represents hydrogen or C1-4alkyl-; R13 represents Ar6-sulfonyl or C1-6alkyloxycarbonyl optionally substituted with phenyl; R16 and R17 represents hydr

Abstract: A method of registering or de-registering, by an optical line terminal (OLT), one or more optical network units (ONUs) in an optical communications network. The method may include: setting one or more sub-channels for registration or de-registration among two or more sub-channels, and a size of a contention window in the one or more sub-channels; transmitting, to one or more ONUs, a registration information message including information of the one or more set sub-channels and the size of the contention window; receiving, through one of the set sub-channels, a registration or de-registration request message from the one or more ONUs, which receive the registration information message; and registering and de-registering the one or more ONUs.

Abstract: Systems and methods are disclosed that generally pertain to provisioning an optical network unit (ONU) by an optical line terminal (OLT) of a passive optical network (PON). An exemplary provisioning system includes a wireless reader incorporated into the ONU and a transponder unit attached to a fiber optic cable coupled to the ONU. The transponder unit includes a storage element in which is stored provisioning information, such a registration ID associated with the ONU. The wireless reader automatically obtains the provisioning information from the transponder when the fiber optic cable is coupled to the ONU and transmits the provisioning information to the OLT via the fiber optic cable as a part of a discovery procedure. The transmission of the provisioning information in this manner eliminates the need for a service technician to visit a customer premise and manually provide the provisioning information via a POTS port of the ONU.

Abstract: The present invention discloses a method and an apparatus for measuring quality parameters of optical transmission channels. The apparatus comprises: a tunable optical filter for receiving an optical signal, performing wavelength or optical carrier demultiplexing on the optical signal, and out-of-band ASE noise suppression; an optical coherent receiver connected to the tunable optical filter, for performing polarization- and phase-diversity detection on the filtered optical signal and converting it into multiple lane baseband electrical signals; analog-to-digital converters for sampling and quantizing the multiple lane baseband electrical signals so as to convert the them into multiple lane digital signals; a digital signal processing module for processing the multiple lane digital signals to obtain quality parameters; and an display module for displaying the quality parameters.

Abstract: A method of setting up an end-to end connection between two end-points in an optical network. A plurality of validated paths in the network are defined. Each validated path extends between a respective pair of wavelength termination points and has requisite physical resources to carry signal traffic between its pair of wavelength termination points. A graph of the network is generated. An edge of the graph corresponds with a respective validated path, and a vertex of the of the graph corresponds with at least one wavelength termination point. The graph is analyzed to compute an end-to-end path between two vertices respectively corresponding with end-points of the end-to-end connection, and the end-to-end connection set up using the computed path.

Abstract: Provided is a method of saving power in a passive optical network (PON) system including an optical line terminal (OLT) and a plurality of optical network units (ONUs), the OLT including an optical transceiver to communicate with at least one ONU through an optical line, and a controller to control the optical transceiver to transmit an upstream bandwidth map to the ONU at a predetermined transmission interval, wherein the transmission interval is determined based on a desired upstream data service delay time.

Abstract: The present invention discloses a method and a controller for commissioning a wave division multiplexing optical network during capacity expansion.

Abstract: An optical line terminal (OLT) coupled to a plurality of optical network units (ONUs) through a passive optical network (PON). The OLT includes a transceiver configured to communicate via a management channel of a communication network with a plurality of OLTs. The communication includes sending or receiving a notification, wherein the notification includes the following: a source OLT identifier associated with a source OLT sending the notification, wherein the source OLT is configured to communicate over a first channel at a first wavelength of the PON; a destination OLT identifier associated with a destination OLT receiving the notification, wherein the destination OLT is configured to communicate over a second channel at a second wavelength of the PON; and an ONU identifier associated with a first ONU associated with the notification.

Abstract: A transmission apparatus includes: a module configured to receive and transmit data externally, the data received and to be transmitted being transferred via an interface internally; a framer configured to process transmission and reception of the data processed by the module; a transmission channel on which predetermined data is transmitted and received to and from the framer; and a controller configured to determine a combination of setting values for transmission and reception in accordance with a surrounding environment of the transmission channel, based on an error rate when the predetermined data is transmitted and received for each combination of setting values for transmission and reception on the transmission channel, and to perform setting for transmission and reception via the interface, based on the determined combination of setting values for transmission and reception.

Abstract: Digital communication systems utilizing entangled qubits are disclosed. The disclosed systems and component sending devices and receiving devices exploit selective entanglement swapping to transfer an entangled state between the sending device and the receiving device. Each device includes pairs of qubits that are independently entangled with pairs of qubits in the other device. By selectively entangling the qubits within a pair in the sending device, the qubits of the corresponding pair in the receiving device also are selectively entangled. When the qubits are entangled, they are projected onto a particular entangled state type. Though no information may be transferred through selective entanglement of one qubit pair, systems of the present disclosure determine whether a set of pairs of qubits are entangled by determining whether the distribution of pairs is a correlated or uncorrelated distribution (a probabilistic approach) and transform the distribution type to a classical bit of data.

Abstract: An optical fiber breakage point may be located by coupling to the optical fiber an out-of-band optical test signal modulated at a periodic modulation pattern. A distance to the breakage point may be determined from a difference between modulation patterns of transmitted and received test signals.

Abstract: A dual-polarization, 2-subcarriers code orthogonal, orthogonal frequency division multiplexed signal carrying information bits is transmitted in an optical communication network without transmitting a corresponding pilot tone or training sequence. A receiver receives the transmitted signal and recovers information bits using a blind equalization technique and by equalizing the 2-subcarriers OFDM signal as a 49-QAM signal in time domain with a CMMA (constant multi modulus algorithm) equalization method.

Abstract: A signal monitoring device, a signal transmission/reception device and a communication device, which realize easy acquisition of a diagnosis result and a signal value, and further realize fast acquisition of the diagnosis result. A signal monitoring device includes: a difference value calculator that time-sequentially calculates, for a signal to be monitored, a difference value between a signal value thereof and a previously set threshold; and a storage that updates and stores the time-sequentially calculated difference value in accordance with a previously set rule.

Abstract: Methods and systems for in-band OSNR monitoring include a tunable optical filter to scan a passband of a desired optical channel. The optical power over the passband is measured and digitized to power waveform data. The power waveform data is processed with a digital signal processor to calculate OSNR. Additionally, various implementations accommodate dual polarization modulation formats using a parallel architecture and an alternating sequential architecture.

Abstract: Methods and systems for optical channel monitoring of dual polarization optical signals may use a periodic optical filter to scan a free spectral range of the periodic optical filter. The optical signals may further be tone modulated using frequency or amplitude modulation. From a filtered signal, normalized Stokes vector signals may be generated using a polarimeter. The normalized Stokes vector signals may be digitally processed to identify center frequencies and power levels of individual optical subcarriers.

Abstract: The FC port state machine enhanced by determining if various lanes are configured to be operated in 128 Gbps mode by operating as parallel lanes as indicated by using a reserved bit in a link training field. If so and if all of the ports are 32 Gbps ports and pass training, then four lanes can be combined to form a 128 Gbps link. If the ports are configured for 128 Gbps only operation and at least one lane does not negotiate to 32 Gbps or fails training, the link is not activated and none of the lanes are activated. If the ports are configured to do either 128 Gbps or independent operation and at least one lane cannot operate at 128 Gbps, then the lanes operate independently at the negotiated and trained speed. If the lanes are configured for only independent operation the transceiver develops independent links as negotiated.

Abstract: Systems and methods for digital communication utilizing entangled qubits are disclosed. The disclosed systems and methods exploit selective entanglement swapping to transfer an entangled state between a sending device and a receiving device. Each device includes pairs of qubits that are independently entangled with pairs of qubits in the other device. By selectively entangling the qubits within a pair in the sending device, the qubits of the corresponding pair in the receiving device also are selectively entangled. When the qubits are entangled, they are projected onto a particular entangled state type. Though no information may be transferred through selective entanglement of one qubit pair, systems and methods of the present disclosure determine whether a set of pairs of qubits are entangled by determining whether the distribution of pairs is a correlated or uncorrelated distribution (a probabilistic approach) and transform the distribution type to a classical bit of data.

Abstract: A technique relates to a self-calibration routine for a laser with respect to a multiplexer. Electrical power is stepped up to a filter within the laser while monitoring transmission through multiplexer to store a current and maximum recorded transmission through multiplexer until minimum operating power is reached. If the current transmission through multiplexer at minimum operating power has fallen by more than predefined amount relative to maximum recorded transmission, the electrical power is stepped up to filter until the current transmission is restored to the predefined amount of the maximum recorded transmission, determining self-calibration for a blue edge of the multiplexer pass band.

Abstract: According to one aspect, embodiments of the invention provide a power supply system comprising an input line configured to receive input AC power, a first capacitor coupled to the input line, a second capacitor, a controller, a rectifier having an input coupled to the first capacitor and an output coupled to the second capacitor, the second capacitor further coupled to the controller, and a switch selectively coupled across the first capacitor, and configured to selectively bypass the first capacitor, wherein the controller is configured to detect a voltage across the second capacitor, operate the switch to charge the second capacitor at a first rate if the voltage is above a predetermined threshold, and operate the switch to charge the second capacitor at a second rate if the voltage is below a predetermined threshold.

Abstract: A technique relates to a self-calibration routine for a laser with respect to a multiplexer. Electrical power is stepped up to a filter within the laser while monitoring transmission through multiplexer to store a current and maximum recorded transmission through multiplexer until minimum operating power is reached. If the current transmission through multiplexer at minimum operating power has fallen by more than predefined amount relative to maximum recorded transmission, the electrical power is stepped up to filter until the current transmission is restored to the predefined amount of the maximum recorded transmission, determining self-calibration for a blue edge of the multiplexer pass band.

Abstract: Systems and methods for digital communication utilizing entangled qubits are disclosed. The disclosed systems and methods exploit selective entanglement swapping to transfer an entangled state between sites. Each site includes pairs of qubits that are independently entangled with pairs of qubits at the other site. By selectively entangling the qubits within a pair at one site, the qubits of the corresponding pair at the other site also are selectively entangled. When the qubits are entangled, they are projected onto a particular entangled state type. Though no information may be transferred through selective entanglement of one qubit pair, systems and methods of the present disclosure determine whether a set of pairs of qubits are entangled by determining whether the distribution of pairs is a correlated or uncorrelated distribution (a probabilistic approach) and transform the distribution type to a classical bit of data.

Abstract: In a TDM/WDM-PON using cyclic sleep, a controller in an OLT calculates the total bandwidth in use for each OSU, and compares the total bandwidth with a threshold. If the calculated bandwidth exceeds the threshold, the controller determines the number of ONUs staying in sleep mode among the ONUs managed by the assignor OSU. If such an ONU exists, that ONU is selected as an ONU whose management is to be changed. From the total bandwidth in use of an assignor OSU from which the management is to be changed, a bandwidth allocated to the ONU which is in sleep mode is subtracted to thereby obtain a bandwidth, which will be compared with the threshold. If the calculated bandwidth exceeds the threshold, from among active ONUs managed by the assignor OSU an ONU whose management is to be changed is selected.

Abstract: Disclosed is a synchronization system including a control apparatus and a plurality of terminals connected via a network. The control apparatus includes a transmitting unit that transmits first waiting time information to each of the terminals, where the first waiting time information is synchronization waiting time for a predetermined signal transmitted from the control apparatus to the terminals. Each of the terminals receives the first waiting time information from the control apparatus and receives second waiting time information from another of the terminals. The second waiting time information has been calculated by the other terminal based on the first waiting time information as received by the other terminal. Each terminal calculates a synchronization time for the predetermined signal based on both of the first waiting time information from the control apparatus and the second waiting time information from the other terminal.

Abstract: A network for transporting communication and power is disclosed. 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.

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.

Abstract: Methods, media, and systems are provided for characterizing the synchronization behavior of a slave clock. A sequence of sync packets, usable to synchronize with a grandmaster clock, is transmitted from the grandmaster clock to a slave clock. The sequence of sync packets is modified by dropping one or more sync packets from the sequence, providing a pattern of dropped sync packets. A synchronization output of the slave clock is monitored and, based on the synchronization output, a determination is made as to whether the slave clock is synchronized while the sequence of sync packets is modified. A characterization of the synchronization behavior of the slave clock is stored with respect to the pattern of dropped sync packets. The process may be repeated for various patterns of dropped sync packets.

Abstract: A system for communicating data comprising sender and receiver subsystems; at least one data input; at least one entangled photon source; first photons of the pairs of entangled photons outputted by the at least one photon source being processed by one of the sender or receiver subsystem; second photons of the pairs of entangled photons being processed by the other of the sender or receiver subsystem; a photonic element configured to receive the first photons of the pairs of entangled photons and enable interference therebetween; at least one absorber configured to absorb the first photons after passage through the beam splitter, the absorbance of the first photons operating to transfer the properties of the entanglement to the second photons of the pairs of entangled photons; and a Bell state measurement element operatively associated with the receiver subsystem configured to measure the second photons of the pairs of entangled photons.

Abstract: A method, a network element, and a network include determining excess margin relative to margin needed to insure performance at a nominal guaranteed rate associated with a flexible optical modem configured to communicate over an optical link; causing the flexible optical modem to consume most or all of the excess margin, wherein the capacity increased above the nominal guaranteed rate includes excess capacity; and mapping the excess capacity to one or more logical interfaces for use by a management system, management plane, and/or control plane. The logical interfaces can advantageously be used by the management system, management plane, and/or control plane as one of restoration bandwidth or short-lived bandwidth-on-demand (BOD) connections, such as sub-network connections (SNCs) or label switched paths (LSPs).

Abstract: An OLT includes an OLT control unit that generates a control signal for controlling a power saving operation of an ONU by specifying a different idle period with respect to a first power saving operation in which an optical receiver is operated while an optical transmitter of the ONU is controlled to a power saving state and a second power saving operation for controlling the optical transmitter and the optical receiver to the power saving state, and a station-side transmitter that transmits the control signal generated by the OLT control unit to the ONU. The ONU includes an ONU control unit that receives the control signal via the optical receiver to selectively perform the first power saving operation and the second power saving operation based on the idle period specified by the control signal.

Abstract: Data transmissions between medical devices are governed by various communication protocols. For example, blood glucose measures may be retrieved wirelessly from a continuous glucose monitor in accordance with the ANT wireless communication protocol. Smaller data packets are preferably transferred in a standard data transfer mode which is optimized for speed and power management; whereas, larger data packets are transferred in a file sharing mode. Techniques are presented to address recovering data lost during the standard data transfer mode in an efficient manner and preferably without the use of the file sharing mode.

Abstract: A converged passive optical network (CPON) and a data transmission method are disclosed. The CPON is a combination of a time division multiple access-passive optical network (TDMA-PON) and an orthogonal frequency division multiple access-passive optical network (OFDMA-PON) and is able to dynamically controlling a bandwidth for upstream signal transmission through allocation of multiple subcarriers to each single optical network unit (ONU).

Abstract: Embodiments of the present invention disclose a path selecting method and apparatus. The method includes: computing an end-to-end path for a newly added service according to network topology and a wavelength constraint, and assigning a wavelength to the path; computing performance of each existing service and performance of the newly added service in a network according to physical impairment information collected in the network, where the physical impairment information includes a gain reference spectrum of each optical amplifier in the network; and performing impairment check on performance of each service, and performing path selection for the newly added service according to a result of the impairment check. The apparatus includes a path computation module, a performance computation module and an impairment check module. According to the embodiments, efficiency of network update or rerouting is improved.

Abstract: Identifier information (LLID) of an ONU and transfer instruction information indicating a transmission system as the output destination of a downstream frame are registered in a table (22) in correspondence with each of the destination IDs of the ONUs or user apparatuses connected to the ONUs. Upon receiving a downstream frame from a host apparatus, a frame transfer processing unit (20) acquires an LLID and transfer instruction information corresponding to the destination ID of the downstream frame from the table (22).

Abstract: An optical communication device includes a transmitter having a transmitter port and a receiver having loopback and receiver ports. The transmitter transmits a first multiplexed signal in a first optical spectrum from the transmitter port. The receiver receives the first multiplexed signal in the loopback port and a second multiplexed signal in the receiver port. The second multiplexed signal is in a second optical spectrum different from the first optical spectrum. The receiver includes a demultiplexer in optical communication with the loopback port and the receiver port. The demultiplexer demultiplexes the first and second multiplexed signals received by the loopback and receiver ports.

Abstract: A digital coherent optical receiver executing coherent reception of a phase-modulated optical signal, includes: a moving average section configured to execute a moving average for received data obtained by sampling of the phase-modulated optical signal; a compensator configured to compensate a wavelength dispersion value of the phase data having been executed with the moving average; and a control section configured to determine a moving average frequency to be executed by the moving average section based on the compensated wavelength dispersion value.

Abstract: Techniques are presented herein to setup a wavelength on a path from a source node to a destination node. Cross-talk margin information already computed for one or more installed wavelengths is obtained between the source node and destination node. A total margin as a function of the cross-talk margin information is computed. A determination is then made as to whether to perform non-linear impairment validation of the wavelength based on the total margin. These techniques may be generalized to account for coherent and non-coherent portions of a network.

Abstract: To facilitate routing and wavelength assignment (RWA) in an optical communications network having a given topology of associated nodes and links, a set of system characteristics associated with operating the optical communications network may be determined. Different sets of values may be selected for one or more parameters of an RWA algorithm defined for operating a set of services on the optical communications network, and associated sets of routes and wavelengths that may be assigned to the set of services via the RWA algorithm in accordance with the different sets of values and the set of system characteristics may be determined. The different sets of routes and wavelengths may be compared based on one or more fitness criteria and thereby selected between. A path computation engine of the optical communications network may then be provisioned with the selected set of values for the one or more parameters.

Abstract: Described herein are systems and methods for accurately estimating and removing a carrier frequency offset. One exemplary embodiment relates to a system comprising a frequency offset detection circuit detecting a carrier frequency offset in an optical signal, and a frequency testing circuit calculating an estimated frequency offset value of the carrier frequency offset, wherein the frequency testing circuit removes a carrier phase based on the estimated frequency offset value and recovers the optical signal. Another exemplary embodiment relates to a method comprising detecting a carrier frequency offset in an optical signal, calculating an estimated frequency offset value of the carrier frequency offset, removing a carrier phase based on the estimated frequency offset value, and recovering the optical signal.

Abstract: Methods and systems for decoding a signal include compensating for impairments in a received signal using at least carrier phase estimation, where residual phase error remains after compensation; calculating symbol log-likelihood ratios (LLRs) for symbols in the compensated signal using Monte Carlo integration; demapping the symbols in the compensated signal using the symbol LLRs and extrinsic information from signal decoding to produce one or more estimated codewords; and decoding each estimated codeword with a decoder that generates a decoded codeword and extrinsic information.