采样时钟抖动对超宽带脉冲雷达目标检测性能的影响

摘要

信号采样是超宽带脉冲雷达接收的关键环节,其中采样时钟抖动会引起ADC输出信噪比的下降,继而对雷达目标的检测性能产生一定影响,为此以雷达目标的检测性能为评价原则,研究了高斯白噪声环境中采样时钟抖动引起的信噪比损失,并以匹配滤波检测器和多样本能量积累检测器为对象,详细推导了采样时钟抖动与目标检测概率的关系.据此给出了输出信噪比损失的理论曲线,通过仿真对比分析了不同检测方法下采样时钟抖动对目标检测性能的影响,对超宽带脉冲雷达系统设计中的采样时钟选取有直接指导意义.%Sampling is the key step of UWB (ultra-wideband) pulse radar receiving, and sampling clock jitter leads to the loss of the output signal-to-noise ratio (SNR) of the ADC, which will affect the performance of radar target detection. SNR loss caused by sampling clock jitter under Gaussian white noise was researched for the evaluation of radar target detection performance, and then the relationship between sampling clock jitter and radar target detection probability was derived using matched filter detector (MFD) and multi-sample energy accumulation detector (EAD). Accordingly, the theoretical loss curve of the output SNR was given. The impact of clock jitter on target detection performance with different detection methods was compared and analyzed via simulation, which is of guiding significance to the selection of the sampling clock in the design of the UWB pulse radar system.