Abstract: Aspects of the subject disclosure may include, for example, calculating, by an EEPN compensation system of a coherent optical receiver, at least one metric, wherein the coherent optical receiver includes a chromatic dispersion compensation system configured to digitally compensate for chromatic dispersion relating to a signal, and a carrier phase recovery system configured to digitally recover a carrier phase associated with the signal, and wherein the calculating is based on information that is downstream of the chromatic dispersion compensation system, and utilizing, by the EEPN compensation system, the at least one metric to perform EEPN compensation relating to the signal upstream of the carrier phase recovery system. Other embodiments are disclosed.

Abstract: Aspects of the subject disclosure may include, for example, receiving a plurality of modulated optical wavelengths generated from digital input data and unmodulated optical wavelengths. The one or more of the plurality of modulated optical wavelengths undergo an optical operation and are converted into one or more electrical signals. The optical operation increases a signal to noise ratio (SNR) of the one or more electrical signals to exceed an SNR threshold. Additionally, the one or more electrical signals are processed to produce digital output data. Other embodiments are disclosed.

Abstract: Aspects of the subject disclosure may include, for example, deriving substantially orthogonal optical fields from an output of an optical source, implementing a delay on one of the substantially orthogonal optical fields, resulting in time delayed optical fields, performing coherent detection of the time-delayed optical fields, resolving electrical field signals based on the coherent detection, and causing the electrical field signals to be processed so as to estimate a property of the optical source, wherein estimation of the property facilitates disturbance detection and localization. Other embodiments are disclosed.

Abstract: Aspects of the subject disclosure may include, for example, a device including a detector configured to identify a narrow-band absorption occurring within a signal spectrum of an optical signal propagating through a gaseous medium, wherein the optical signal is configured to communicate digital information via an optical communication link including a transmitter, a receiver and an optical transport medium therebetween. The device further includes a mitigation controller configured to control a digital circuit to mitigate at least a portion of a vulnerability of the optical communication link, the vulnerability associated with the narrow-band absorption. Other embodiments are disclosed.

Abstract: Aspects of the subject disclosure may include, for example, obtaining an estimate of a phase of a reference associated with a signal received over an optical channel, obtaining an estimate of a frequency of a carrier associated with the signal, and based on the estimate of the phase of the reference and the estimate of the frequency of the carrier, estimating a location dependent property associated with a disturbance to the optical channel to determine a location estimate for the disturbance. Other embodiments are disclosed.

Abstract: An optical transmitter device includes a digital signal processor (DSP) having digital hardware. The DSP is operative to generate shaped bits from a first set of information bits, and to apply a systematic forward error correction (FEC) scheme to encode the shaped bits and a second set of information bits, where the first set of information bits and the second set of information bits are disjoint sets. Unshaped bits and the shaped bits are mapped to selected symbols or are used to select symbols from one or more constellations. The selected symbols are mapped to physical dimensions. Each unshaped bit is either one of the second set of information bits or one of multiple parity bits resulting from the FEC encoding. In this manner, a target spectral efficiency is achieved.

Abstract: The process can include generating a first one of an electron gas and a hole gas at the first side of the p-n junction, and generating a second one of the electron gas and the hole gas at the second side of the p-n junction; discontinuing both the electron gas and the hole gas; generating the first one of the electron gas and the hole gas at the second side of the p-n junction; and discontinuing the first one of the electron gas and the hole gas at the second side of the p-n junction.

Abstract: Aspects of the subject disclosure may include, for example, receiving a plurality of modulated optical wavelengths generated from digital input data and unmodulated optical wavelengths. The one or more of the plurality of modulated optical wavelengths undergo an optical operation and are converted into one or more electrical signals. The optical operation increases a signal to noise ratio (SNR) of the one or more electrical signals to exceed an SNR threshold. Additionally, the one or more electrical signals are processed to produce digital output data. Other embodiments are disclosed.

Abstract: Aspects of the subject disclosure may include, for example, deriving substantially orthogonal optical fields from an output of an optical source, implementing a delay on one of the substantially orthogonal optical fields, resulting in time delayed optical fields, performing coherent detection of the time-delayed optical fields, resolving electrical field signals based on the coherent detection, and causing the electrical field signals to be processed so as to estimate a property of the optical source, wherein estimation of the property facilitates disturbance detection and localization. Other embodiments are disclosed.

Abstract: Aspects of the subject disclosure may include, for example, obtaining an estimate of a phase of a reference associated with a signal received over an optical channel, obtaining an estimate of a frequency of a carrier associated with the signal, and based on the estimate of the phase of the reference and the estimate of the frequency of the carrier, estimating a location dependent property associated with a disturbance to the optical channel to determine a location estimate for the disturbance. Other embodiments are disclosed.

Abstract: Aspects of the subject disclosure may include, for example, a device including a detector configured to identify a narrow-band absorption occurring within a signal spectrum of an optical signal propagating through a gaseous medium, wherein the optical signal is configured to communicate digital information via an optical communication link including a transmitter, a receiver and an optical transport medium therebetween. The device further includes a mitigation controller configured to control a digital circuit to mitigate at least a portion of a vulnerability of the optical communication link, the vulnerability associated with the narrow-band absorption. Other embodiments are disclosed.

Abstract: An optical transmitter device includes a digital signal processor (DSP) having digital hardware. The DSP is operative to generate shaped bits from a first set of information bits, and to apply a systematic forward error correction (FEC) scheme to encode the shaped bits and a second set of information bits, where the first set of information bits and the second set of information bits are disjoint sets. Unshaped bits and the shaped bits are mapped to selected symbols or are used to select symbols from one or more constellations. The selected symbols are mapped to physical dimensions. Each unshaped bit is either one of the second set of information bits or one of multiple parity bits resulting from the FEC encoding. In this manner, a target spectral efficiency is achieved.

Abstract: An optical transmitter device (14) includes a digital signal processor ‘DSP’ (20) having digital hardware (30). The DSP is operative to generate (102,202,302) shaped bits from a first set of information bits, and to apply (104,204,304) a systematic forward error correction ‘FEC’ scheme to encode the shaped bits and a second set of information bits, where the first set of information bits and the second set of information bits are disjoint sets. Unshaped bits and the shaped bits are mapped to selected symbols or are used to select symbols from one or more constellations. The selected symbols are mapped to physical dimensions. Each unshaped bit is either one of the second set of information bits or one of multiple parity bits resulting from the FEC encoding. In this manner, a target spectral efficiency is achieved.

Abstract: An optical transmitter device (14) includes a digital signal processor ‘DSP’ (20) having digital hardware (30). The DSP is operative to generate (102,202,302) shaped bits from a first set of information bits, and to apply (104,204,304) a systematic forward error correction ‘FEC’ scheme to encode the shaped bits and a second set of information bits, where the first set of information bits and the second set of information bits are disjoint sets. Unshaped bits and the shaped bits are mapped to selected symbols or are used to select symbols from one or more constellations. The selected symbols are mapped to physical dimensions. Each unshaped bit is either one of the second set of information bits or one of multiple parity bits resulting from the FEC encoding. In this manner, a target spectral efficiency is achieved.

Abstract: A method of estimating nonlinear transmission impairments of an Optical Channel (OCh) trail in an optical communications network. A per-span nonlinear field variance is calculated for each span of the trail. The per-span nonlinear field variance represents nonlinearly induced noise due to the transmission impairments of that span. The nonlinearly induced noise being imparted to a signal transmitted through the trail and detected by the receiver. A respective covariance between the nonlinear fields contributed by each span pair of the OCh trail is computed. The covariance represents the correlation of the nonlinearly induced noise imparted to the signal within the first span of a span pair with the nonlinearly induced noise imparted to the signal within the second span of the pair. A covariance matrix is populated using the computed per-span variance values and covariance values. A total nonlinear field variance is computed by summing over the covariance matrix elements.