Crosstalk characteristics of resonant dispersion EDFAs in WDM systems

The nonlinear Schrödinger equation is solved using the small signal analysis approach. In the resonant dispersion erbium-doped fiber amplifiers (EDFAs) of WDM systems, the crosstalk between signals and induced by signals are discussed. The resonant dispersion of EDFAs has a strong effect on the cross-phase modulation instability gain frequency, and causes severe crosstalk when the multiple signal channels are taken into account. In a WDM system, for most channels where the resonant dispersion occurs, the crosstalk powers induced by other channels' XPM are stronger than the intensity modulation induced by XPM between the reference and other channels. The factors affecting crosstalk include signal power, nonlinear coefficient and channel separation. Pump power distribution can dominantly diminish crosstalk. To keep the system's performance, the proper dispersion compensation is a better method to minimize the crosstalk.