A 40-Gb/s optical time division multiplexing (OTDM) return-to-zero (RZ) transmission experiments including a dynamic polarization mode dispersion (PMD) compensation was reported. The dynamic PMD compensator is made up of two-stage four degrees of freedom (DOF). The first stage adopts polarization controller and fixed time-delayed line. The second stage is variable differential group delay (DGD) element. The PMD monitoring technique is based on degree of polarization (DOP) as error signal. A novel practical adaptive optimization algorithm was introduced in dynamic adaptive PMD compensation. The experimental results show that the performance of the PMD compensator is excellent for 40-Gb/s RZ transmission systems with the large DGD. With this compensator, a significant improvement of system performance can be achieved in the eye pattern of a received signal. The first-order compensating ability of the compensator is greater than 30 ps. The second-order compensating ability is greater than 200 ps2. The first-order optimum compensating time is within 10 ms. The second-order optimum compensating time is within 24 ms.
© 2005 Chinese Optics Letters
Tangjun Li, Muguang Wang, Shuisheng Jian, Caiyun Lou, Li Huo, Hejun Yao, Tigang Ning, Jie Cui, Fangcheng Yang, Cao Diao, Xiangfeng Gong, Yongjun Fu, Zhongwei Tan, and Yan Liu, "Dynamic PMD compensation in 40-Gb/s optical communication system," Chin. Opt. Lett. 3, 264-267 (2005)