Analysis of Self and Cross-Phase Modulation Effect in Optical WDM System with Dispersion Compensation

Fiber Optic Communication System is undoubtedly the most prospective system as it can provide huge bandwidth comparative to other existing communication system i.e. high frequency microwave transmission. But fiber optic communication system suffers from fiber loss, different dispersive effects like Group Velocity Dispersion (GVD), Material Dispersion and Waveguide Dispersion and nonlinear effects like Self-Phase Modulation (SPM) and Cross-Phase Modulation (XPM) and from mutual interplay between these effects as well. In this work, a WDM fiber optic communication system with Intensity Modulation and Direct Detection (IM-DD) has been investigated at both 10 Gb/s and 40 Gb/s considering GVD, SPM and XPM with loss and GVD being compensated periodically. Since SPM-GVD and XPM-GVD interactions depend on input channel power, a thorough investigation of transmission performance has been carried out taking different input power. Eye opening diagram has been determined and eye penalty and cross-talk have been calculated for different input power with variable length of transmission fiber link. Suppression of SPM and XPM effects has also been investigated using initially chirped input waveform and through dispersion management. Through a detailed study, it has been found that, SPM and XPM seriously limit the transmission performance of a WDM transmission link at high input power, and SPM and XPM effects can be considerably reduced using prechirping and optimum dispersion management.