Improved FWM Efficiency for Already Deployed Bidirectional Fiber Optic Cable using Polarization Manipulation for Underwater Applications

Optical communication is vastly used in underwater communication systems. It is more efficient to use bidirectional cables rather than two different cables for two way communication. This research is carried out to satisfy the curiosity that what can be done to improve already deployed bidirectional optical networks. In this paper polarization manipulation is used to reduce Four Wave Mixing in bidirectional fiber cable in already deployed DWDM system for underwater applications. Only one component is added to previously used systems, circular polarizer. Circular polarizers are used alternately to change the polarization of incoming pulses into right handed and left handed polarizations. Simulations are carried out in “Opti system” software at 10 Gbps using bidirectional fiber optics cable having 8 channels. System's performance is analyzed on the basis of four wave mixing efficiency, BER, Q factor, received power and eye diagram. Results show that 10 dB of reduction in FWM efficiency is observed at downlink and 7 dB in uplink while improving Q factor and BER at the same time.