背向瑞利散射是光纤中一种重要的物理过程，利用该物理现象实现的光时域反射计是一种重要且常见的光纤测量设备.本文理论研究了任意波形的输入脉冲在光纤中的背向瑞利散射过程，导出了将瑞利散射看作为一种线性系统的冲激响应函数，讨论了方波与有振荡拖尾的注入脉冲的背向散射输出波形.对于方波注入，利用商用光时域反射仪表对理论进行了验证；对于有拖尾的脉冲，进行了实验研究，结果表明仿真与实验结果一致.

Rayleigh backscattering is an important physical process in optical fibers, and the Optical Time Domain Reflectometer (OTDR) based on the rayleigh backscattering, is one of the most important and widely-used optical fiber measuring equipments. Rayleigh backscattering progress with arbitrary input optical pulses in the fiber was analyzed theoretically, the impulse response function was derived on the basis of regarding fiber as a linear system, and backscattered output pulse of square pulse and pulse with vibrating was discussed. For the square pulse, the theory of impulse response was demonstrated by commercial OTDR instrument. For the pulse with vibrating, the experimental results show a good agreement with the simulation.