激光告警接收机灵敏度和信噪比分析及实验验证

Analysis and Experimental Verification of Sensitivity and SNR of Laser Warning Receiver

为了对抗现代战争中日趋严重的激光威胁,激光告警技术已成为亟需研究的课题之一。灵敏度和信噪比是激光告警系统重要的性能指标,它直接影响告警系统整体的探测性能。文中根据信号统计检测理论,提出了一种计算相干探测光谱识别型激光告警接收机灵敏度和信噪比的方法。首先,分析了激光信号和接收机噪声的概率分布。然后,基于阈值探测理论和奈曼—皮尔逊准则,通过引入探测概率因子和虚警概率因子,建立了信号电流方程,进而得到了灵敏度和信噪比的计算表达式。最后,利用该方法对自行研制的光栅衍射激光告警接收机的探测灵敏度和信噪比进行了理论计算和相关的实验验证,结果表明:由该方法计算的灵敏度和信噪比与实验结果基本相符。

In order to countermeasure increasingly serious threat from hostile laser in modern war,it is urgent to do research on laser warning technology and system,and the sensitivity and signal to noise ratio（SNR） are two important performance parameters in laser warning system.In the present paper,based on the signal statistical detection theory,a method for calculation of the sensitivity and SNR in coherent detection laser warning receiver（LWR） has been proposed.Firstly,the probabilities of the laser signal and receiver noise were analyzed.Secondly,based on the threshold detection theory and Neyman-Pearson criteria,the signal current equation was established by introducing detection probability factor and false alarm rate factor,then,the mathematical expressions of sensitivity and SNR were deduced.Finally,by using method,the sensitivity and SNR of the sinusoidal grating laser warning receiver developed by our group were analyzed,and the theoretic calculation and experimental results indicate that the SNR analysis method is feasible,and can be used in performance analysis of LWR.