基于光纤中高相干光源（相干长度大于100 km）的瑞利散射光的统计特性，采用随机相向量模型，推导了光纤中瑞利散射光的功率分布和相位分布，指出瑞利散射光功率的概率密度函数(PDF)符合修正的莱斯分布，而瑞利散射光的相位分布近似为高斯分布。采用高灵敏度的光电探测器对不同长度的光纤的瑞利散射光功率进行了测试，实验结果与理论吻合，同时发现不同长度光纤的瑞利散射光功率的最大值随平均值线性增加。

Statistical properties of the Rayleigh backscattered light power and phase caused by a highly coherent semiconductor laser from single-mode fiber are presented. Based on the random phasor model, the results show that the probability density function (PDF) of Rayleigh backscattered light power from single-mode fiber follows the modified Rician distribution. The phase distribution of Rayleigh scattered light is approximately Gaussian distribution. The experimental results are shown to correspond to theoretical derivation, and the maximum power of scattered light from different lengths increases linearly with the mean intensity.