Suppression of four wave mixing by optical phase conjugation in DWDM fiber optic link

The dominating effect of Wavelength Division multiplexed system is Four Wave Mixing (FWM). Channel crosstalk and performance degradation of the system can be induced in the multi channel systems by FWM. In this paper, the FWM affecting the original Dense Wavelength Division Multiplexed (DWDM) signal power is studied and suppression of FWM is achieved by placing the Optical Phase Conjugator (OPC) in the midway of the fiber optic link. It strongly suppresses the FWM signal by introducing the destructive interference between the first and second halves of the fiber optic link. Reconstruction of original signal can be achieved by placing another OPC at the end of the second fiber span. DWDM system with OPC can effectively suppress the Four Wave Mixing signal power.