Adjustable gain controlled SOA for optical burst receiver

Burst mode receiver in a packet transmission through an optical fiber encounters the problem of large amplitude fluctuation among the incoming bursty data packets which causes an optical amplifier to deviate from its linearity. To mitigate this problem, an adjustable gain controlled semiconductor optical amplifier (AGC-SOA) can be employed as a preamplifier to the burst mode receiver. In this paper, a simple model consisting of two SOAs and a laser cavity loop is used to implement an AGC-SOA. It is observed from the simulated results that, the model is capable of providing linearity over almost 30dB range of input packet power, which is wide enough to be used in burst receiver. The results also show the occurrence of a constant value of output saturation power as high as 1dBm. Reservoir model of SOA is employed to simulate the behaviour of AGC-SOA and the results match with the reported data [6] quite accurately.