Evaluating higher-order four-wave mixing effect using a two-channel WDM system

Summary form only given. To suppress four-wave mixing (FWM) induced cross talk in wavelength-division multiplexed (WDM) systems in dispersion-shifted fiber (DSF), the unequal channel-spacing scheme was proposed and works quite well for most cases because it avoids generating FWM products to fall on to any channels. However, the newly produced FWM products can mix with channel signals or themselves to produce higher-order FWM products which can overlap with channels and result in crosstalk. In this presentation, we show that these FWM products can become a serious problem as channel power increases or channel spacing decreases.