Dynamic gain variations in discrete fiber Raman amplifiers subject to multi-channel packet traffic

In this paper, we study the behavior of discrete fiber Raman amplifiers fed by multi-channel packet traffic. Precisely, we apply the gain-clamping technique in order to know if it can reduce the gain transients occurring at the output of the amplifier. We study both unclamped and gain-clamped amplifiers in a WDM situation using 64 WDM channels of which one is non-varying. We start by investigating the influence of the standard deviation of the input power Gaussian distribution when the amplifiers are operated in the small-signal regime. Next, we analyze the impact of the packet duration on the transients by using packet durations of 25 and 100 μs. Finally, by increasing the per channel input power, we study the impact of the operational regime on the gain transients characteristics.