FWM Mitigation in DWDM Optical Networks

Abstract

In this paper, three optical communication systems have been proposed to mitigate Four Wave Mixing (FWM). Three techniques are used, namely; low input power with high gain amplifier, a collective Optical Time Division Multiplexing (OTDM) and Dense Wavelength Division Multiplexing (DWDM) system, and the use of alternative circular polarization. The first technique involves reduction in input power to -20 dBm and then amplifying it 40 dB before demultiplexing. The second technique divides the input signal into four time slots and then combine them with a power combiner. In the third technique, the polarization of light coming from input channels is changed after modulation into right and left handed circular polarization. Exhaustive sets of simulations are performaed using Optisys. The performance analysis includes Q-factor, Optical Signal to Noise Ratio (OSNR), received optical power, minmum Bit Error Rate (BER) and eye diagram.