在双环耦合全光缓存器的基础上分析了全光分组交换网络中以半导体光放大器(SOA)为相移器件的反馈型全光缓存器输出的信号损伤,包括SOA的非线性及载流子恢复时间限制引起的脉冲畸变与连续码流中的图样失真和SOA的自发辐射噪声累积引起的信噪比恶化及缓存器结构引起的"漏光"问题.理论分析及实验结果表明,在采用反相控制并注入高功率控制光的情况下,脉冲畸变与图样失真被抑制,由信噪比恶化及漏光决定的光分组的缓存圈数被限制在20—30圈.得到的结果对基于SOA的光缓存器及逻辑器件同样具有借鉴作用.
This paper analyzes the signals impairment in the semiconductor optical amplifier (SOA) based optical buffer for optical packets switching networks,including the shape distortion of single pulse and the pattern dependent distortion of the continuous bit stream due to the SOA's nonlinearity and the limitation of its carrier lifetime,the deterioration of signal-to-noise ratio caused by the accumulation of amplified spontaneous emmision noise of the SOA,and the power leakage. The theoretical analysis and experimental results indicate that the buffered circle is restricted to 20—30,as determined by the signals impairment when a negative control optical pulse with high power is injected into SOA.