Transparent wavelength conversion for a novel orthogonal FSK/IM modulation format at 40-Gb/s based on FWM effect of SOA

We numerically investigate a transparent wavelength conversion for a high-speed orthogonal frequency-shift keying and intensity-modulated (FSK/IM) modulation format based on four-wave-mixing (FWM) in semiconductor optical amplifier (SOA). The inter-band and intra-band carrier dynamics, such as gain saturation, carrier density pulsation (CDP), carrier heating (CH) and spectral hole burning (SHB) have all been taken into account in our in-house SOA model. Simulation results show that about 3.5-dB and 1.5-dB power penalty at BER of 1e-9 can be achieved for the 40-Gb/s FSK payload and 2.5-Gb/s IM label after conversion. With fixed signal wavelength, the 1-dB sensitivity penalty range of the pump wavelength for the payload and label can be observed at the value of 4-nm and 5.6-nm respectively. Additionally, the dynamic range of IM modulation depth from 0.3 to 0.8 can also be observed after conversion.