It is found that selecting appropriate value of duty cycles of Gauss light pulse signal, frequency chirp and the roll-off factor of raised cosine pulse signal produced by the equalizer of an optical receiver can improve the sensitivity of the optical receiver. 发现适当选取高斯光脉冲信号的占空比、啁啾分量、光接收机均衡滤波器输出的升余弦频谱波形滚降因子的值可以提高光接收机灵敏度;