信号偏振度反馈控制偏振模色散补偿的解析研究

基于主偏振态理论和一阶近似，导出了光路的偏振模色散引起信号偏振度下降的简洁解析表达式．它能处理多种因素对偏振度下降的影响，包括信号啁啾、升降时间、放大自发辐射、脉冲波形和消光比等．通过我们的仿真数据与实验结果的比较，验证了它的正确性．数值仿真也表明利用信号偏振度监测和控制偏振模色散的DOP技术能有效补偿差分群延迟小于1．54个位周期的光通信系统的偏振模色散。

A general analytical approach to signal degree of polarization used as feedback contro1 in PMD compensation

Based on principal state of polarization (PSP) theory and first-order approximation, we derive a compact analytical expression of the degree of polarization (DOP) degradation of optical signal induced by the polarization mode dispersion (PMD) of the optical link. Our analytical approach can handle the effects of various factors of the DOP degradation, such as signal chirp, rise/fall time, amplified spontaneous emission (ASE) noise, waveform, extinction ratio, and so on. The validity of our analytic approach has been demonstrated by the comparison between our numerical simulation and the reported experiments. The simulations also show that the DOP method, which uses the signal DOP to monitor and control PMD, can compensate the PMD effects in optical communication systems with the amount of differential group delay (DGD) smaller than 1.5 bit time.