Distributed Nonlinearity Compensation of Dual-Polarization Signals Using Optoelectronics

We propose an optoelectronic method for the distributed compensation of nonlinear fiber distortions affecting polarization multiplexed signals. This method involves placing devices we call total-intensity-directed phase modulators at the start of each amplified fiber span, in order to compensate the effect of fiber nonlinearity on a span-by-span basis. Numerical simulations are used to compare our proposed method with the well-known digital back propagation (DBP) algorithm for a wavelength division multiplexed system consisting of eight dual-polarization 16QAM channels operating at 28 GBd transmitted through a 15 × 100 km dispersion unmanaged link. These simulations show that the proposed distributed nonlinearity compensation technique increases the peak signal quality, Q, by 1 dB while DBP only increases peak Q by 0.5 dB.