Minimization of the effect of cross phase modulation on a WDM optical transmission system

Abstract

Cross phase modulation (XPM) is the most serious effect that limits the allowable input power and system capacity by generating intensity modulated power causing more noise at the receiver in long-haul multichannel light-wave DWDM transmission system. In this thesis line coding schemes are applied to combat the effect of XPM in a DWDM optical system. Multilevel line coding schemes like duobinary and Novel optical line codes are analyzed in. detail to get an insight to their effect in data transmission. The XPM effect is also analyzed to quantify its effect in terms of realizable parameters. Performance criteria are expressed in terms of bit error rate (BER) and eye-opening penalty (EOP). Performances of line coding are evaluated for different parameters like different fiber lengths, channel spacing and input powers. Analytical and simulated results show 1.89 dB improvements in terms of input power.