基于多重重要抽样法的联合偏振效应功率代价计算

Computation of power penalty due to combined polarization effects using multiple importance sampling

采用重要抽样法研究了偏振模式色散(PMD)和偏振相关损耗(PDL)对10Gbps OOK和DPSK光纤通信系统的影响,计算了在误码率为10-12时的功率代价和系统失效概率.仿真结果表明系统失效概率随偏振相关损耗成指数增长.在其它条件相同的情况下,DPSK系统性能总是优于OOK系统.当设定功率余量为3 dB和失效概率为10-6时,在PMD=20 ps,DPSK和OOK系统对偏振相关损耗忍受度分别可达1.25 dB和0.8 dB左右.

The effects of polarization-mode dispersion and polarization-dependent loss on 10 Gbps systems with two modulation formats are investigated using multiple importance sampling. The power penalties at fixed biterror ratio of 10 - 12 and system outages are computed. The simulation results show that the system outage almost increases exponentially with the increase of the polarization-dependent loss. It is found that the differential phase shift keying modulation always performs better than the on-off keying modulation under the same conditions. When 3 dB power margin and 10-6 outage probability are set, the differential phase shift keying and the on-off keying can resist the polarization-dependent loss up to about 1.25 dB and 0.8 dB respectively even if the average polarization-mode dispersion is 20 ps.