光学学报, 2009, 29 (s2): 175, 网络出版: 2010-01-27
20 Gb/s差分四相移键控系统偏振模色散自适应补偿实验研究
Experimental Research of Adaptive PMD Compensator for 20 Gb/s DQPSK System
光纤通信 差分四相移键控(DQPSK) 偏振模色散 自适应补偿 fiber optic communication DQPSK polarization mode dispersion adaptive compensation
摘要
随着光纤通信系统速率的不断提高,光纤中的偏振模色散(PMD)逐渐成为限制光纤通信系统性能的主要因素之一。当系统的传输速率达到40和100 Gb/s时,缓解偏振模色散对信号的损伤成为必要。报道了以偏振度(DOP)作为反馈信号,粒子群优化算法(PSO)作为搜索跟踪算法的两阶段光偏振模色散自适应补偿器,并将其分别应用于20 Gb/s 非归零差分四相移键控及载波抑制差分四相移键控系统。通过多次搜索和长时间跟踪验证了偏振模色散自适应补偿器的性能。搜索成功率接近100%,搜索过程中平均动作次数在100次以内,最大耗时在30 ms以内;跟踪过程中,在快速扰偏的情况下,作为反馈信号的偏振度始终保持在1附近。成功实现了对造成差分群时延(DGD)最大可达89 ps快速变化的动态一阶和部分高阶偏振模色散的自适应补偿和实时跟踪,具有很强的实用价值。
Abstract
For upgrading the existing 100 Gb/s fiber optic communication systems to 40 Gb/s or beyond systems smoothly, research on polarization mode dispersion (PMD) compensators is becoming a hot topic nowadays. Adaptive PMD compensation is successfully demonstrated in 20 Gb/s NRZ-DQPSK and CSRZ-DQPSK system. The research realizes quick searching and real time tracking by using degree of polarization (DOP) as the feed back signal and adopting the particle swarm optimization (PSO) algorithm under rapid polarization scramble. Experimental results show that time-varying PMD which has the largest differential group delay(DGD) of 89 ps in the transmission link is successfully mitigated by the adaptive PMD compensators.
翁轩, 张晓光, 席丽霞, 赵鑫媛, 田凤. 20 Gb/s差分四相移键控系统偏振模色散自适应补偿实验研究[J]. 光学学报, 2009, 29(s2): 175. Weng Xuan, Zhang Xiaoguang, Xi Lixia, Zhao Xinyuan, Tian Feng. Experimental Research of Adaptive PMD Compensator for 20 Gb/s DQPSK System[J]. Acta Optica Sinica, 2009, 29(s2): 175.