研制了一台探测大气温度、气溶胶、卷云的瑞利-拉曼-米氏激光雷达(RRML),介绍了激光雷达的设计方法,基于单片机实现了光电倍增管门控电路。通过数值模拟计算大气后向散射回波信号,分析仿真信号的特征,作为激光雷达设计的参考。通过设计合理的接收光路,采用极高灵敏度的R4632光电倍增管以及微弱信号光子计数技术,提高瑞利和拉曼微弱信号的信噪比(SNR)。为了实现瑞利-拉曼-米氏激光雷达对大气气溶胶和卷云的联合探测,532 nm回波信号采取高低分层技术,通过对气溶胶和卷云的回波光加衰减和探测器门控两种手段相结合,保证了R4632光电培增管极高的灵敏度探测器对大气气溶胶和高层卷云回波信号的线性检测,从而实现一台激光雷达对大气温度、气溶胶和卷云的探测。试验表明,信号检测单元的设计满足测量精度的要求。

A Rayleigh-Raman-Mie lidar (RRML) signal detection and optical receiver unit is constructed,the principle of lidar design is emphatically introduced,the design is based on the simulated calculation on atmosphere backscatter signal. The purpose of the signal detection unit is to improve the signal to noise ratio (SNR) of the lidar signal. By rational design the signal detection and optical receiver unit,use extremely sensitive R4632 photomultiplier tube (PMT) and photo counting method,a good SNR of Raman and Rayleigh signal could received. Through construct the PMT gating control and signal attenuation unit,a linear detection of aerosol and cirrus signal is received. Finally,the experimental result shows the rationality of the signal detection and optical receiver unit design method.