Systems and methods for the compensation of nonlinear cross polarization and cross phase modulation in dual polarization coherent channels

摘要

The present disclosure provides systems and methods for the compensation of signal distortion in fiber optic communication systems and the like. More specifically, the present disclosure provides an orthogonal polarization detection and broadband pilot (OPDBP) technique for the compensation of nonlinear cross polarization (i.e. nonlinear cross polarization modulation) (XPolM) induced noise and nonlinear nonlinear cross phase modulation (XPM) induced noise in a high data rate polarization multiplexed (PM) multilevel-quadrature amplitude modulated (M-QAM) channel due to neighboring channels. This approach allows for the compensation of both XPolM and XPM simultaneously, providing several dBs of optical reach extension. The approach uses a pilot tone based orthogonal polarization detection scheme with broadband (i.e. a few GHz wide) filtering of the pilot tones.

主权项

1. A method, in a receiver, for compensation of nonlinear cross phase polarization and cross phase modulation in a dual polarization coherent optical system, the method comprising:
receiving a dual polarization optical signal with two pilot tones, each of the two pilot tones is i) at a different frequency thereby avoiding mixing during propagation from the transmitter and ii) in a same State of Polarization (SOP) as respective data signals associated with the dual polarization optical signal; obtaining a Horizontal polarization (H-pol) pilot and a Vertical (V-pol) polarization pilot from the received dual polarization optical signal; and determining scalar products using the H-pol pilot, the V-pol pilot, and a signal pilot, wherein the scalar products are indicative of fast nonlinear cross polarization modulation-induced polarization variations and nonlinear cross phase modulation-induced phase variations during the propagation, for use in the compensation.