Self-Phase Modulation Compensation in Optical OFDM System Based on Wavelet

Abstract

Self-Phase Modulation (SPM) can not be ignored in single light source OFDM system, so it is necessary to overcome the influence of SPM. A joint equalization solution to optical OFDM system based on orthogonal wavelet transform is proposed in this paper. In this method, block pilots are periodically inserted into the frame of OFDM signals. At receiver, the phase rotations of pilots are extracted to pre-compensation. Then, Maximum Likelihood Sequence Estimation (MLSE) equalizer based on Voterra is applied to compensation the SPM. Simulation results demonstrate that the proposed method is effective for 100 Gbit/s optical 16QAM-OFDM system in which the G.652 fiber with nonlinear coefficient of 2.6 /w/km is used.