Abstract: A method for per-span optical fiber nonlinearity compensation comprises determining values of fiber parameters characterizing one or more target optical fibers in one or more respective spans of a link, and applying selected weight values to one or more photonic computing chips (PCCs), each PCC integrated in a different respective span of the link, wherein selection of the weight values is based on the values of the fiber parameters and a mapping associated with each PCC. The method further comprises transmitting an optical signal through the link, wherein each integrated PCC emulates an inverse of a nonlinear transfer function of the target optical fiber in the respective span, thereby reducing nonlinearity contributed by the one or more target optical fibers to the optical signal.

Abstract: A method of loading a fiber optic transport system includes detecting optical power in a frequency sub-band of optical spectrum, wherein the frequency sub-band includes data-bearing channels and at least one control channel; measuring optical power in the frequency sub-band; and adjusting optical power of the at least one control channel based on the measured optical power, wherein the optical power is adjusted through one of changing a current of control channel lasers and controlling a set of fast optical attenuators.

Abstract: A system configured to perform a method for estimating external noise in a communication channel between a transmitter and a receiver is described. The method comprises obtaining a measurement of effective noise on decoded symbols at the receiver, the decoded symbols comprising noisy versions of symbols conveyed by a communication signal transmitted over the communication channel. The method further comprises storing a representation of a relationship between the effective noise, external noise in the communication channel, and one or more variable parameters. The method further comprises storing applicable values of the variable parameters, wherein each applicable value is associated with current properties of the transmitter or current properties of the receiver or both. The method further comprises calculating an estimate of the external noise in the communication channel using the effective noise, the applicable values of the variable parameters, and the representation of the relationship.

Abstract: A system configured to perform a method for estimating external noise in a communication channel between a transmitter and a receiver is described. The method comprises obtaining a measurement of effective noise on decoded symbols at the receiver, the decoded symbols comprising noisy versions of symbols conveyed by a communication signal transmitted over the communication channel. The method further comprises storing a representation of a relationship between the effective noise, external noise in the communication channel, and one or more variable parameters. The method further comprises storing applicable values of the variable parameters, wherein each applicable value is associated with current properties of the transmitter or current properties of the receiver or both. The method further comprises calculating an estimate of the external noise in the communication channel using the effective noise, the applicable values of the variable parameters, and the representation of the relationship.

Abstract: A processor of an apparatus is configured to apply one or more control algorithms using estimated data to adjust the one or more control parameters of a section of an optical fiber network. The estimated data are derived from measurements of optical signals in the section and from knowledge of the section. The estimated data is a function of optical nonlinearity and of amplified spontaneous emission.

Abstract: A system for loading a fiber optic transport system includes a wavelength selective switch (WSS) having inputs and an output connected to an optical fiber, wherein the inputs are connected to one or more lines having data-bearing channels thereon; and an amplified spontaneous emission (ASE) generator connected to one of the inputs of the WSS, wherein the WSS is configured to perform a channel addition through substitution of an ASE channel from the ASE generator for a data-bearing channel, and a channel deletion through substitution of a data-bearing channel for an ASE channel from the ASE generator, and wherein, to limit perturbations on the optical fiber due to channel additions and deletions, the WSS is configured to limit a number of channels that are switched at a same time for a set of channel additions or deletions.

Abstract: A system for loading a fiber optic transport system includes a wavelength selective switch (WSS) having inputs and an output connected to an optical fiber, wherein the inputs are connected to one or more lines having data-bearing channels thereon; and an amplified spontaneous emission (ASE) generator connected to one of the inputs of the WSS, wherein the WSS is configured to perform a channel addition through substitution of an ASE channel from the ASE generator for a data-bearing channel, and a channel deletion through substitution of a data-bearing channel for an ASE channel from the ASE generator, and wherein, to limit perturbations on the optical fiber due to channel additions and deletions, the WSS is configured to limit a number of channels that are switched at a same time for a set of channel additions or deletions.

Abstract: A processor of an apparatus is configured to apply one or more control algorithms using estimated data to adjust the one or more control parameters of a section of an optical fiber network. The estimated data are derived from measurements of optical signals in the section and from knowledge of the section. The estimated data is a function of optical nonlinearity and of amplified spontaneous emission.

Abstract: A processor of an apparatus is configured to apply one or more control algorithms using estimated data to adjust the one or more control parameters of a section of an optical fiber network. The estimated data are derived from measurements of optical signals in the section and from knowledge of the section. The estimated data is a function of optical nonlinearity and of amplified spontaneous emission.

Abstract: A method of loading a fiber optic transport system includes detecting optical power in a frequency sub-band of optical spectrum, wherein the frequency sub-band includes data-bearing channels and at least one control channel; measuring optical power in the frequency sub-band; and adjusting optical power of the at least one control channel based on the measured optical power, wherein the optical power is adjusted through one of changing a current of control channel lasers and controlling a set of fast optical attenuators.

Abstract: A method of loading a fiber optic transport system includes adding one or more control channels to an optical fiber having one or more channels, wherein each of the control channels comprises a pair of signals that are cross-polarized and each of the pair of signals is at a different frequency from one another; measuring optical power on the optical fiber; and adjusting optical power of the one or more control channels based on the measured optical power.

Abstract: A processor of an apparatus is configured to apply one or more control algorithms using estimated data to adjust the one or more control parameters of a section of an optical fiber network. The estimated data are derived from measurements of optical signals in the section and from knowledge of the section. The estimated data is a function of optical nonlinearity and of amplified spontaneous emission.

Abstract: Adjustment of one or more control parameters of a section of an optical fiber network involves taking measurements of optical signals in the section, deriving estimated data from the measurements and from knowledge of the section, where the estimated data is a function of optical nonlinearity and of amplified spontaneous emission, and applying one or more control algorithms using the estimated data to adjust the one or more control parameters.

Abstract: Adjustment of one or more control parameters of a section of an optical fiber network involves taking measurements of optical signals in the section, deriving estimated data from the measurements and from knowledge of the section, where the estimated data is a function of optical nonlinearity and of amplified spontaneous emission, and applying one or more control algorithms using the estimated data to adjust the one or more control parameters.

Abstract: A method of loading a fiber optic transport system includes adding one or more control channels to an optical fiber having one or more channels, wherein each of the control channels comprises a pair of signals that are cross-polarized and each of the pair of signals is at a different frequency from one another; measuring optical power on the optical fiber; and adjusting optical power of the one or more control channels based on the measured optical power.

Abstract: A method and system for transient and switching stabilization of a fiber optic transport system. One or more data-bearing channels are coupled to an optical fiber. The data-bearing channels are distributed among a plurality of frequency sub-bands. A set of control channels is also coupled to the optical fiber. Each control channel includes a pair of signals at separate frequencies. There is at least one control channel in each of the plurality of frequency sub-bands. The pair of signals of a control channel are cross-polarized. Optical power in at least one of the plurality of sub-bands is measured. Responsive to the measured optical power, the optical power of a control channel is adjusted to maintain a substantially constant power of a sub-band that contains the adjusted control channel.

Abstract: Flexible optical spectrum management systems and methods in an optical network including a plurality of interconnected network elements include determining an associated frequency/wavelength center and one or more bins for each of one or more traffic carrying channels on each of a plurality of optical fibers in the optical network; and managing the one or more traffic carrying channels on the plurality of optical fibers using the one or more bins of bins and the associated frequency/wavelength center, wherein at least one of the one or more traffic carrying channels comprises a coherent optical signal occupying a flexible spectrum on the plurality of optical fibers.

Abstract: Flexible optical spectrum management systems and methods in an optical network including a plurality of interconnected network elements include determining an associated frequency/wavelength center and one or more bins for each of one or more traffic carrying channels on each of a plurality of optical fibers in the optical network; and managing the one or more traffic carrying channels on the plurality of optical fibers using the one or more bins of bins and the associated frequency/wavelength center, wherein at least one of the one or more traffic carrying channels comprises a coherent optical signal occupying a flexible spectrum on the plurality of optical fibers.

Abstract: The present disclosure relates to concatenated optical spectrum transmission systems and methods that allocate optical spectrum of groups of channels to reduce or eliminate deadbands or guardbands (i.e., unused optical spectrum) between channels. The concatenated optical spectrum transmission systems and methods include various techniques for using optical spectrum such as over the C-band or any other frequency bands. In particular, the concatenated optical spectrum transmission systems and methods provide a balance between fixed channel systems such as provided for by the International Telecommunication Union (ITU) and a more flexible system enabled by coherent optical detection. In an exemplary embodiment, the concatenated optical spectrum transmission systems and methods may utilize a Wavelength Selective Switch (WSS) and a plurality of moderate Common Mode Rejection Ratio (CMRR) coherent receivers in combination to achieve a concatenated optical spectrum.

Abstract: A network element includes an electronic switch for routing traffic between a plurality of client access ports and a plurality of EO ports, a respective EO interface coupled to each one of the plurality of EO ports; a wavelength selective switch for optically switching optical signals between the EO interfaces and a set of optical transmission fibers; and a control system. The plurality of EO interfaces includes at least one Make Before Break (MBB) EO interface. The control system is operative to reconfigure the network element by identifying an EO interface to be reconfigured. A new optical path is set up through the wavelength selective switch and terminated on the MBB EO interface. The electronic switch is then controlled to re-route a traffic flow traversing the identified EO interface to the MBB EO interface.