脉冲激光测距回波特性及测距误差研究

Echo Characteristics and Range Error for Pulse Laser Ranging

对于飞行目标轨迹测量中常用的脉冲激光测距系统,回光波形的变化对其测距精度的影响尤为显著。为了研究回光波形变化造成的测距误差,深入分析了复杂三维飞行目标的回波特性。以典型的调Q脉冲激光测距为基础,探讨了调Q脉冲激光发射脉冲的数学描述,建立了一种通过飞行目标的反射特性、表面形状及姿态信息计算回波功率分布的理论模型。在此基础上,以典型目标为例建立了目标模型,通过仿真模拟研究了脉冲激光回波特性,分析了目标姿态变化对回波特性及回波畸变测距误差的影响。搭建了脉冲激光测距实验系统,加工制作了模拟目标并进行了验证实验。实验结果表明,飞行目标姿态变化引起的回波脉冲展宽及回波畸变测距误差变化规律与理论分析基本一致,验证了所建理论模型的有效性。

For the pulse laser ranging system commonly used in flight target trajectory measurement,the variation of echo waveforms has significant effect on the ranging accuracy.In order to study the range error caused by the variation of echo waveforms,we analyze the echo characteristics of the complex three-dimensional flying target.Based on the typical Q-switched pulsed laser ranging,the mathematical model of transmitted pulse of Q-switched laser is analyzed,and a theoretical model is presented with echo power distribution calculated by the reflection characteristics,surface shape and orientation information of the flying target.On the basis of the above,the target model is built with a typical target,and the characteristics of pulsed laser echo are studied by simulation.The influence of target orientation on echo characteristics and echo distortion range error is analyzed.The pulse laser ranging experiment system is built and the simulated target is processed for verification experiment.The experimental results show that the echo pulse broadening and distortion range error caused by attitude angles variation of flight target are consistent with the basic theory,which verifies the effectiveness of the model.