用电功率反馈控制信号实现10Gbit/s系统的PMD补偿实验

光纤通信线路检测到的电功率随差分群延迟变化, 可以作为PMD补偿的反馈控制信号.给出了这一变化关系的理论计算和曲线并通过实验验证这一关系, 确定电压信号与DGD的变化关系.建立了一套完整的实验系统, 并考虑了影响反馈电压信号的多种因素以及减小这些影响的措施.眼图给出的实验结果说明了补偿的效果, 还利用误码测试仪测量了补偿前后的接收灵敏度的改变以定量说明补偿的效果, 最后比较了不同情况下的补偿结果.

Experiments of PMD Compensation Using Electrical Feedback Signals for a 10Gbit/s System

Electrical power, changing with differential group delay (DGD) and detected from an optical communication link, can be used as feedback signals of compensating for PMD. Theoretical calculations and curves are given representing the change of electrical power with DGD. Experimental results confirming the theoretical calculations are presented for voltage V changing with DGD. A setup is built for experiments of PMD compensations. Several factors affecting the feedback signals are proposed and methods are given to make the fluctuations less. Results of PMD compensation prototype for a 10 Gb/s pseudo random sequence are shown through eye patterns. These results are also shown by receiver sensitivity improvements after compensation. Receiver sensitivity under 3 different bit error rates are measured using BER measuring equipment. Comparisons of results using different fibers are made, confirming the effectiveness of compensation.