利用动态方程研究了偏振模色散矢量的统计特性 ,分别用统计系综和频率系综两种方法进行数值模拟。数值结果表明 ,统计系综和频率系综两种方法的结果一致。在大归一化距离条件下 ,均方根时延的平方随归一化距离线性变化 ;偏振模色散矢量的各个分量服从高斯分布 ,差分群时延服从麦克斯韦分布 ;偏振模色散矢量弥散于整个邦加球 The dynamic characteristics are used to study the statistical properties of PMDs. Two methods, statistical ensemble and frequency ensemble, are used to simulate the PMDs. The numerical results show that the results of the two methods of statistical ensemble and frequency ensemble are consistent. Under the condition of large normalized distance, the square of the rms delay linearly changes with the normalized distance. The components of polarization mode dispersion obey the Gaussian distribution, the differential group delay obeys Maxwell distribution, and the polarization mode dispersion vector disperses in the whole Bangalore