Investigation of the intensity noise reduction using a saturated semiconductor optical amplifier in spectrum sliced WDM systems

Summary form only given. Intensity noise in spectrum-sliced WDM systems utilizing incoherent broadband sources imposes strong limits on the achievable system performances. Techniques for reducing the intensity noise using a saturated SOA have recently been proposed and experimentally demonstrated. We have investigated and optimized these techniques using a saturated gain-clamped SOA (GC-SOA). The influence of the gain-saturation level and the bias current of the SOA on the noise reduction has been studied experimentally, and the optimum condition for a high noise suppression ratio has been derived. A noise reduction of 18 dB at low frequencies and 10 dB at high frequencies was obtained, which is much better than that given in the literature (10 dB at low frequencies).