相干测风激光雷达回波偏振态对径向风速精度影响  

Influence of echo polarization of coherent wind LiDAR on radial wind speed accuracy

作　　者：彭涛[1] 王顺艳[1] 王丹凤 范琪 罗雄[1] 周鼎富[1] PENG Tao;WANG Shunyan;WANG Danfeng;FAN Qi;LUO Xiong;ZHOU Dingfu(Southwest Institute of Technical Physics,Chengdu 610041,China)

机构地区：[1]西南技术物理研究所,成都610041

出　　处：《激光技术》2024年第5期613-619,共7页Laser Technology

摘　　要：为了解决大气退偏效应造成激光回波与本振光偏振失配,导致相干测风激光雷达(LiDAR)外差效率降低的问题,基于相干多普勒激光测风雷达的系统组成和工作原理,采用数学建模法,仿真分析了回波偏振态对系统信噪比、探测距离和径向风速误差的影响;提出了偏振态修正途径,并利用琼斯矩阵建模讨论修正精度;用径向风速比对实验验证不同回波偏振态对径向风速精度的影响。结果表明,对于同一测试系统,在相同的天气条件下,与回波为圆偏振态相比,回波为椭圆偏振态时的最大探测距离下降46.7%,径向风速精度下降63%。此研究为相干多普勒测风激光雷达回波接收模块的优化提供了理论支撑。In order to solve the polarization mismatch between echo and local oscillator caused by the atmospheric depolarization effect leading to a decrease in heterodyne efficiency of coherent wind light detection and ranging(LiDAR),the influence of echo polarization on signal-to-noise ratio and ranges and radial wind speed error was simulated using mathematical modeling method,based on the system composition and working principle of coherent Doppler wind LiDAR.By proposing a polarization state correction approach and using Jones matrix,a model was built to discuss the correction accuracy.According to the comparative test of radial wind speed,the influence of different echo polarization on radial wind speed accuracy was verified.The results show that for the same system and weather,if the echo is elliptical polarization,the maximum range will decrease by 46.7%and the radial wind speed accuracy will decrease by 63%compared to the circular polarization.This study provides theoretical support for the optimization of echo receiving module of coherent Doppler wind LiDAR.

关 键 词：激光技术 径向风速精度 验证实验 回波偏振态 

分 类 号：TN958.98[电子电信—信号与信息处理] TN249[电子电信—信息与通信工程]