CO_2激光成像雷达距离分辨率测距精度的分析与实验研究

Analysis and Experiment of the Distance Resolving Power and Measure Accuracy of the CO_2 Imaging Lidar

分析了脉冲外差体制CO2 激光成像雷达系统的目标距离分辨率、测距精度和误差的主要来源 对于单个光脉冲测距来讲 ,信噪比 (SNR)起伏引起的探测误差、脉冲前沿触发等概率分布以及脉冲建立时间的随机性等是激光脉冲外差测距的主要随机误差 ,其它随机误差在数量级上可忽略不计 同时利用现有的CO2 激光脉冲外差探测系统 ,进行了远目标测距对比实验 ,观测到了 2 35 5m目标脉冲回波信号 ,并精确测量出CO2 光脉冲飞行的往返时间 。

The distance resolving power and measure accuracy and the main error source of a CO 2 pulse-heterodyne detecting system are analyzed. For ranging with single pulse of the heterodyne signal, the main random errors derive from fluctuation of SNR (signal noise ratio) and instability of trigger front and pulse generating time while the other errors can be ignored. Using the existing CO 2 pulse heterodyne detecting system,the contrastive experiment of ranging the targets far away is carried out,pulse echo signal from target 2355 meters away is observed,the cruise time of laser pulse is measured accurately. The experiment data can be used to proofread and compensate the systematic error.