Abstract: A system is configured to measure a forward error correction (FEC) decoding property associated with applying FEC decoding to FEC-encoded bits or symbols at a receiver device deployed in a communication network. The system is further configured to provide an assessment of operating conditions of the receiver device based on the FEC decoding property. In one example, the FEC decoding property comprises a distribution of a number of iterations of a FEC decoding operation applied to a plurality of FEC blocks processed within a period of time. In some examples, the FEC decoding property comprises any one of heat, temperature, current, voltage, active clock cycles, idle clock cycles, activity of parallel engines, activity of pipeline stages, and input or output buffer fill level of the FEC decoding. In some examples, the assessment is based on a comparison between the FEC decoding property and reference FEC data.

Abstract: An optical transmitter (102,200) is operable to generate an optical signal (260) by modulating a number N of frequency divisional multiplexing (FDM) subcarriers using transformed digital signals which are determined by applying a pseudo FDM (pFDM) transformation to preliminary digital signals representative of multi-bit symbols. Rather than experiencing the effects of the number N of FDM channels, the optical signal experiences the effects of a different number M of pFDM channels, where M?N. In some examples, the number M of pFDM channels is less than the number N of FDM channels, and frequency-dependent degradations may be averaged across different symbol streams. In other examples, the number M of pFDM channels is greater than the number N of FDM channels, and different symbol streams may experience different frequency-dependent degradations. An optical receiver (102,300) is operable to apply an inverse pFDM transformation to recover estimates of the multi-bit symbols.

Abstract: Systems and method include a detector communicatively coupled to a fiber span; and processing circuitry connected to the detector and configured to digitally sample and process an output of the detector, detect phase changes in the output, and identify an electrostrictive response of the fiber span based on the detected phase changes and based on a dependence of the detected phase changes with frequency. A property of the fiber span can be determined on the electrostrictive response. The property of the optical fiber can include one or more of optical fiber material type, optical fiber material property, optical fiber area, optical fiber geometry, optical fiber condition, optical fiber stress and strain, optical fiber temperature. and optical fiber radiation exposure.

Abstract: An optical transmitter (102,200) is operable to generate an optical signal (260) by modulating a number N of frequency divisional multiplexing (FDM) subcarriers using transformed digital signals which are determined by applying a pseudo FDM (pFDM) transformation to preliminary digital signals representative of multi-bit symbols. Rather than experiencing the effects of the number N of FDM channels, the optical signal experiences the effects of a different number M of pFDM channels, where M?N. In some examples, the number M of pFDM channels is less than the number N of FDM channels, and frequency-dependent degradations may be averaged across different symbol streams. In other examples, the number M of pFDM channels is greater than the number N of FDM channels, and different symbol streams may experience different frequency-dependent degradations. An optical receiver (102,300) is operable to apply an inverse pFDM transformation to recover estimates of the multi-bit symbols.

Abstract: Systems and methods include a transmitter configured to communicate over an optical link to a receiver; and a controller configured to, with the transmitter and the receiver operating in a first operating mode, obtain measurements related to operation over the optical link, determine statistical properties of the optical link based on the measurements, wherein the statistical properties relate to conditions on the optical link, and set a second operating mode of one or more of the transmitter and the receiver based on the determined statistical properties. Each of the first operating mode and the second operating mode refer to associated settings in one or more of the transmitter and the receiver, and there is a trade-off between the first operating mode and the second operating mode and associated margin on the optical link.

Abstract: Systems and method include a detector communicatively coupled to a fiber span; and processing circuitry connected to the detector and configured to digitally sample and process an output of the detector, detect phase changes in the output, and identify an electrostrictive response of the fiber span based on the detected phase changes and based on a dependence of the detected phase changes with frequency. A property of the fiber span can be determined on the electrostrictive response. The property of the optical fiber can include one or more of optical fiber material type, optical fiber material property, optical fiber area, optical fiber geometry, optical fiber condition, optical fiber stress and strain, optical fiber temperature. and optical fiber radiation exposure.

Abstract: Systems and methods include a transmitter configured to communicate over an optical link to a receiver; and a controller configured to, with the transmitter and the receiver operating in a first operating mode, obtain measurements related to operation over the optical link, determine statistical properties of the optical link based on the measurements, wherein the statistical properties relate to conditions on the optical link, and set a second operating mode of one or more of the transmitter and the receiver based on the determined statistical properties. Each of the first operating mode and the second operating mode refer to associated settings in one or more of the transmitter and the receiver, and there is a trade-off between the first operating mode and the second operating mode and associated margin on the optical link.

Abstract: Methods and assemblies for determining a property or environment of an optical fiber, including: measuring a frequency dependent electrostrictive response of an optical fiber; and based on the measured frequency dependent electrostrictive response, determining a property of the optical fiber. The property or environment of the optical fiber includes one or more of optical fiber type, optical fiber material type, optical fiber material property, optical fiber area, optical fiber geometry, optical fiber condition, optical fiber stress and strain, optical fiber environment, optical fiber temperature, optical fiber routing, optical fiber spooling, and optical fiber radiation exposure.

Abstract: An optical transmitter is operable to generate an optical signal by modulating a number N of frequency divisional multiplexing (FDM) subcarriers using transformed digital signals which are determined by applying a pseudo FDM (pFDM) transformation to preliminary digital signals representative of multi-bit symbols. Rather than experiencing the effects of the number N of FDM channels, the optical signal experiences the effects of a different number M of pFDM channels, where M?N. In some examples, the number M of pFDM channels is less than the number N of FDM channels, and frequency-dependent degradations may be averaged across different symbol streams. In other examples, the number M of pFDM channels is greater than the number N of FDM channels, and different symbol streams may experience different frequency-dependent degradations. An optical receiver is operable to apply an inverse pFDM transformation in order to recover estimates of the multi-bit symbols.

Abstract: Systems and methods for operating an optical modem include operating with first operating settings; and, responsive to detection or expectation of a disturbance in an operating condition associated with the optical modem, operating with second operating settings for a time period based on statistical properties of the disturbance. The systems and methods can further include reverting to the first operating settings after the time period. The disturbance can be a polarization transient or a transient affecting a laser or a clock. The second operating settings can cause a reduced margin relative to the first operating settings for the time period.

Abstract: Methods and assemblies for determining a property or environment of an optical fiber, including: measuring a frequency dependent electrostrictive response of an optical fiber; and based on the measured frequency dependent electrostrictive response, determining a property of the optical fiber. The property or environment of the optical fiber includes one or more of optical fiber type, optical fiber material type, optical fiber material property, optical fiber area, optical fiber geometry, optical fiber condition, optical fiber stress and strain, optical fiber environment, optical fiber temperature, optical fiber routing, optical fiber spooling, and optical fiber radiation exposure.

Abstract: Using pump-probe measurements on multi-span optical links may result in the determination of one or more of the following: 1) wavelength-dependent power profile and gain evolution along the optical link; 2) wavelength-dependent dispersion map; and 3) location of regions of high polarization-dependent loss (PDL) and polarization-mode dispersion (PMD). Such measurements may be a useful diagnostic for maintenance and upgrade activities on deployed cables as well as for commissioning new cables.

Abstract: Systems and methods for distributed measurement in a network implemented by an orchestrator include directing one or more modules associated with one or more network elements to each perform a subset of the distributed measurement; receiving results from at least one network element of the one or more network elements based on the directing; and detecting an event or property based on the results. The subset of the distributed measurement can be based on performance monitoring data.

Abstract: An optical module adapted to operate in an optical network to perform an optical function therein includes optical components adapted to perform one or more functions associated with the optical module; processing circuitry communicatively coupled to the optical components and adapted to obtain data generated during operation of the one or more functions; and compute resources communicatively coupled to the processing circuitry and adapted to receive an application for local execution on the compute resources in a sandboxed manner, and analyze, by the application, the data to perform one or more functions.

Abstract: Using pump-probe measurements on multi-span optical links may result in the determination of one or more of the following: 1) wavelength-dependent power profile and gain evolution along the optical link; 2) wavelength-dependent dispersion map; and 3) location of regions of high polarization-dependent loss (PDL) and polarization-mode dispersion (PMD). Such measurements may be a useful diagnostic for maintenance and upgrade activities on deployed cables as well as for commissioning new cables.

Abstract: An optical module adapted to operate in an optical network to perform an optical function therein includes optical components adapted to perform one or more functions associated with the optical module; processing circuitry communicatively coupled to the optical components and adapted to obtain data generated during operation of the one or more functions; and compute resources communicatively coupled to the processing circuitry and adapted to receive an application for local execution on the compute resources in a sandboxed manner, and analyze, by the application, the data to perform one or more functions.

Abstract: Using pump-probe measurements on multi-span optical links may result in the determination of one or more of the following: 1) wavelength-dependent power profile and gain evolution along the optical link; 2) wavelength-dependent dispersion map; and 3) location of regions of high polarization-dependent loss (PDL) and polarization-mode dispersion (PMD). Such measurements may be a useful diagnostic for maintenance and upgrade activities on deployed cables as well as for commissioning new cables.

Abstract: Using pump-probe measurements on multi-span optical links may result in the determination of one or more of the following: 1) wavelength-dependent power profile and gain evolution along the optical link; 2) wavelength-dependent dispersion map; and 3) location of regions of high polarization-dependent loss (PDL) and polarization-mode dispersion (PMD). Such measurements may be a useful diagnostic for maintenance and upgrade activities on deployed cables as well as for commissioning new cables.

Abstract: Techniques for transmitting a data signal through an optical communications system. An encoder is configured to encode the data signal to generate symbols to be modulated onto an optical carrier. Each symbol encodes multiple bits of data and includes a first portion selected from a first constellation and a second portion selected from a second constellation. The first and second constellations have respective different average amplitudes. Each of the first and second constellations have a cardinality of at least two and the cardinality of the first constellation is greater than the cardinality of the second constellation. A modulator is configured to modulate a first frame of the optical signal using the first portion and modulate a second frame of the optical signal using the second portion. A selection of one frame of the optical signal to be used as the first frame encodes at least 1 bit of data.

Abstract: Techniques for transmitting a data signal through an optical communications system. An encoder is configured to encode the data signal to generate symbols to be modulated onto an optical carrier. Each symbol encodes multiple bits of data and includes a first portion selected from a first constellation and a second portion selected from a second constellation. The first and second constellations have respective different average amplitudes. Each of the first and second constellations have a cardinality of at least two and the cardinality of the first constellation is greater than the cardinality of the second constellation. A modulator is configured to modulate a first frame of the optical signal using the first portion and modulate a second frame of the optical signal using the second portion. A selection of one frame of the optical signal to be used as the first frame encodes at least I bit of data.