Regenerative 80-Gb/s fiber XPM wavelength converter using a hybrid Raman/EDFA gain-enhanced configuration

Regenerative wavelength conversion at 80 Gb/s using distributed Raman gain and cross-phase modulation (XPM) in 1 km of highly nonlinear dispersion-shifted fiber is demonstrated. Raman gain greatly enhances the fiber nonlinearity by changing the power evolution along the fiber and meanwhile maintains the signal-to-noise ratio of the wavelength converted signal due to the effect of distributed gain on optimizing cross-phase versus self-phase modulation. Bit-error-rate measurements were performed both before and after wavelength conversion, with a negative power penalty of 2 dB at 10/sup -9/ bit-error rate for return-to-zero formats. The reshaping properties of this wavelength converter were clearly demonstrated in both the frequency and time domain.