光数字相干接收机中色散补偿模块设计与优化

Design and Optimization of Chromatic Dispersion Compensation Block in Digital Coherent Optical Receiver

在高速光纤通信数字相干接收系统中,色散补偿模块的结构和性能将直接决定其是否具有实用价值。设计了比传统的有限脉冲响应(FIR)滤波器结构简单的偶对称型FIR滤波器,并通过数值仿真分析了FIR滤波器长度选取对补偿效果的影响。研究结果表明,在接收端光信噪比(OSNR)代价不高于1dB的情况下,FIR滤波器长度折衷选取为最大值的65%,这样既能有效地补偿色散损伤,又可以降低FIR滤波器实现的复杂度。

In digital coherent receivers of high-speed optical fiber communication, the structure and performance of chromatic dispersion compensation block determines its practical value directly. A finite impulse response （FIR） filter with simpler even-symmetric structure is designed, and the effect of different lengths of FIR filter on chromatic dispersion compensation performance is discussed through numerical simulation. The results show that the length of FIR filter can be reduced to 65 percent of its theoretical maximum with only 1 dB penalty of optical signal-to-noise ratio （OSNR） at the receiver, in which the implementation complexity is decreased at a large scale while chromatic dispersion impairment can be compensated effectively.