基于空间辐射和器件辐射效应的特点，选取正态分布对辐射的剂量率和单位辐射剂量造成的性能退化量进行描述，得到了卫星光通信系统中半导体激光器的可靠度函数。进而以高轨空间辐射条件为背景，对器件的性能退化量进行了模拟，在模拟数据的基础上利用最大似然估计法计算性能退化量的分布函数，得到了器件的可靠度曲线以及平均寿命。最后分析了减少测试时间，以较少的样本数量进行估计的可行性。

Laser diode is the preferred laser source for satellite laser communication system, and it is significant to analyze its reliability in space radiation environment. According to the character of space radiation and devices′ radiation dose, normal distribution is used to describe both space radiation dose rate and performance degradation per unit radiation dose, and the reliability function of laser diode is achieved. The performance degradation in high- orbit radiation environment is simulated. On the basis of the simulated data, devices′ distribution function is evaluated by maximum likelihood estimate, and then the reliability curve and average life are obtained. The feasibility of using less experimental time and less sample number to evaluate distribution function is analyzed.