Compensation of interchannel nonlinearities using enhanced coupled equations for digital backward propagation

Enhanced coupled-nonlinear equations are introduced for full compensation of cross-phase modulation and partial compensation of four-wave mixing (FWM) via split-step digital backward propagation. Compared to full FWM compensation, the new backward propagation equations provide a significant reduction in the number of steps required in the split-step method. This increased step size together with more relaxed sampling requirements reduced the computational load by more than a factor of 20.