Optical dispersion compensation in the electrical domain in an optical communications system

A method of compensating chromatic dispersion of a communications signal conveyed through an optical communications system, the method comprising:

• deriving a compensation function that mitigates a substantial portion of the chromatic dispersion imparted to the communications signal by the optical communications system;
• digitally processing a digital input signal using the compensation function to generate a predistorted signal;
• processing the predistorted signal using a non-linear compensator to generate a further distorted signal comprising a pair of orthogonal signal components;
• and
• modulating an amplitude and a phase of an optical signal using the pair of orthogonal signal components of the further distorted signal to generate a corresponding predistorted optical signal for transmission through the optical communications system,
• wherein the non-linear compensator is configured to substantially compensate for nonlinearities in one or both of an optical modulator of a transmitter of the optical communications system and an optical-to-electrical converter of a receiver of the optical communications system.

A dispersion compensation system for compensating chromatic dispersion of a communications signal conveyed through an optical communications system, the dispersion compensation system comprising:

• a processor configured to derive a compensation function that mitigates a substantial portion of the chromatic dispersion imparted to the communications signal by the optical communications system;
• a compensation processor configured to digitally process a digital input signal using the compensation function to generate a predistorted signal comprising a pair of orthogonal signal components;
• and
• a multi-dimensional optical modulator configured to modulate an amplitude and a phase of an optical signal using the pair of orthogonal signal components of the predistorted signal to generate a corresponding predistorted optical signal for transmission through the optical communications system.

A dispersion compensation system for compensating chromatic dispersion of a communications signal conveyed through an optical communications system, the method comprising:

• a processor configured to derive a compensation function that mitigates a substantial portion of the chromatic dispersion imparted to the communications signal by the optical communications system;
• a compensation processor configured to digitally process a digital input signal using the compensation function to generate a predistorted signal;
• a non-linear compensator configured to process the predistorted signal to generate a further distorted signal comprising a pair of orthogonal signal components;
• and
• a multi-dimensional optical modulator configured to modulate an amplitude and a phase of an optical signal using the pair of orthogonal signal components of the further distorted signal to generate a corresponding predistorted optical signal for transmission through the optical communications system,
• wherein the non-linear compensator is configured to substantially compensate for nonlinearities in one or both of an optical modulator of a transmitter of the optical communications system and an optical-to-electrical converter of a receiver of the optical communications system.