色散管理传输系统中克尔效应对偏振模色散的补偿研究

光纤的随机双折射效应可导致脉冲无规展宽即偏振模色散(PMD)。在零路径色散管理孤子传输系统中，二阶色散和三阶色散效应均被完全补偿，克尔效应成为一种有害因素会使脉冲变窄，但是当光纤的随机双折射被考虑时，克尔效应正好与PMD相互抵消，使光脉冲准稳定传输，不同的光纤偏振模色散参数分别对应不同的最佳系统功率。此外，如果考虑不同偏振方向的损耗差异，则即使在最佳匹配条件下，微小的偏振损耗差异也可产生很大的脉宽波动。因此，偏振相关损耗是影响脉冲传输质量的相当重要的因素，不论在理论计算还是在工程设计中都应当认真考虑。

Compensation of Polarization Mode Dispersion by Means of Kerr Effect in Dispersion-managed Systems

Randomly varying birefringence in optical fiber can lead to pulse broadening, corresponding to polarization-mode dispersion (PMD) effect. Here the interaction between random birefringence and Kerr effect is investigated numerically about dispersion-managed (DM) soli-ton. In zero-averaged-path dispersion managed optical fiber links, because linear dispersion is full compensated, the Kerr effect becomes a detrimental factor in the transmitting system of DM soltion and makes optical pulse narrower. However, when random birefringence is considered, Kerr effect appropriately resists pulse broadening induced by PMD. Systems performance can be improved greatly, as long as PMD is compensated by the nonlinear effect through suitable birefringence parameter and systems power. In addition, considering polarization-dependent losses (PDL), the results show that the fluctuation and broadening of pulse width arc very large even with little loss difference in two polarization directions. So, PDL must be considered in high-bit-rate optical fiber communication systems.