Effects of gain modulation on wavelength conversion using four-wave mixing in semiconductor optical amplifiers

We investigate the converted OSNR, the ISI, and the BER performance of all-optical wavelength converter based on FWM in SOA's as functions of the input pump and signal powers. We demonstrate that the converted OSNR and the ISI are two main factors in the BER performance of the wavelength converter. The minimum power penalty of less than 0.6 dB is achieved by optimizing of the input pump and signal power. We also study the important issue of the dynamic range of input signal power. Two approaches to expand the dynamic range have been presented with the resulting dynamic ranges of more than 25 dB and 12 dB respectively and both show good tolerance to variations in input signal power. Index Terms. wavelength conversion, gain modulation, four-wave-mixing, semiconductor optical amplifiers, dynamic range.