Investigation of FWM effect on BER in WDM optical communication system with different modulation formats

This paper simulates two-channel WDM optical communication system to investigate the effect of FWM on Bit Error Rate (BER) for different Non-Return to Zero (NRZ) and Return to Zero (RZ) type of modulation formats at various dispersion values and core effective area of fiber for optical link having two spans of 100 km each. BER got improved with NRZ raised cosine modulation format and by increasing the core effective area of fiber. A fuzzy based approach is proposed to calculate BER using NRZ raised cosine modulator by varying the dispersion and core effective area of fiber. Fuzzy logic helps in dealing with uncertain and complex systems difficult to model mathematically.