采样时钟抖动在弱光信号检测中的影响分析

摘要

信号采样是弱光信号检测的关键技术环节，由于采样时钟抖动引起的采样信号的输出误差会影响后续的信号检测和处理。为此，分析了输入光信号为近高斯分布波形时由时钟抖动引起的采样误差，推导出了采样输出的信噪比损失公式，讨论了采样带宽、输入信噪比以及信号脉宽对输出信噪比损失的影响，最后以取样积分检测技术为对象，计算了在不同累积次数的条件下采样抖动对取样积分检测性能的影响，对弱光信号检测中的采样时钟选取具有一定的指导意义。%Sampling is the key technology of the weak optical signal detection. However,the sampling output signal er-ror due to the sampling clock jitter will affect the signal detection and processing. Therefore,the sampling error due to the clock jitter is analyzed when the input signal is the Gauss distribution. Accordingly,the loss of the sampling output signal-to-noise (SNR)is obtained,and the influence of the sampling bandwidth,input SNR and the signal duration on the loss of the output SNR is discussed. In the end,the effect of sampling jitter on the sampling integral detection probability is calculated with different accumulation number,which provides the guidance for the select of sampling clock in the weaken optical signal detection.