Fiber nonlinearity mitigation in optical links that use OFDM for dispersion compensation

Abstract—The nonlinear power limit of optical links using optical orthogonal frequency division multiplexing for dispersion compensation can be significantly improved using a simple and computationally efficient nonlinearity precompensation technique that requires no additional optical components. Simulations show that a 2-dB increase in transmission power is possible for 6 ps/nm/km fibers in a 4000-km system, and this increases to 4 dB for 2 ps/nm/km fibers. Alternatively, the bit error ratio can be substantially reduced with precompensation when the systems are operated at an optimum power. Only a single tuning parameter is used to represent the whole link, and the system is robust against variations in this parameter. Index Terms—Electronic dispersion compensation (EDC), fiber nonlinearity, modulation, optical communications, orthogonal fre-quency division multiplexing (OFDM). I