40Gb/s光通信系统中光域偏振模色散补偿的实验研究

Optical Domain PMD Compensation in 40Gb/s Optical Communication System

在 4 0Gb s归零码 (RZ)大PolarizationModeDispersion(PMD)光通信系统中 ,采用两级四自由度光域PMD(偏振模色散 )补偿器 ,以信号的DOP(偏振度 )为反馈信号 ,利用自适应优化算法 ,实现了一阶及高阶PMD动态自适应补偿 .最大一阶PMD补偿能力为 35ps ,二阶PMD补偿能力为 2 0 0ps2 ,PMD动态自适应补偿器的优化补偿时间小于1 0ms.

An experiment of two-stages four degrees high-order PMD compensation in 40Gb/s RZ optical communication system with a large PMD is achieved.The former stage adopts polarization controller and fixed time-delayed line of PMF.The second stage consists of a polarization rotator and a magneto-optical-crystal of tunable DGDs that are used to compensate remnant first-order PMD.The PMD monitoring technique is based on DOP as error signal.A novel practical adaptive optimization algorithm was introduced in dynamic adaptive PMD compensation.The experimental results show the improvement in PMD.With this compensator,a significant improvement of system performance can be achieved in the eye pattern of a received signal.Most first-order compensating ability of the compensator is 35 ps.Second-order compensating ability of the compensator is 200ps2.The optimum compensating time is within several milliseconds.