Fiber-nonlinearity pre-compensation processing for an optical transmitter

Abstract

An optical transmitter configured to mitigate the adverse effects of fiber nonlinearity by altering the transmitted constellation symbols based on specific nonlinear characteristics of a fiber-optic link over which the optical transmitter is configured to transmit and on an a priori estimate of the nonlinear component of the optical-signal distortion in that fiber-optic link. In an example embodiment, each constellation symbol is altered by a respective perturbation amount determined using (i) a calculated or measured nonlinear transfer function corresponding to the fiber-optic link and (ii) a set of neighboring constellation symbols that are expected to contribute to the nonlinear distortion of the optical signal carrying the present constellation symbol due to the fiber nonlinearity. In various embodiments, different appropriate perturbation amounts can be selected to approximately pre-compensate nonlinear distortions caused by various nonlinear optical effects, such as four-wave mixing, etc.

Dependencies are inferred from the claim text.