基于Golay脉冲编码技术的相干激光雷达仿真研究

Simulation Research of Coherent Lidar Based on Golay Coding Technology

针对相干激光雷达远场回波信号信噪比低,提取困难的问题,提出了脉冲编码技术,以改善系统信噪比,增大雷达探测距离。研究了相干激光雷达系统中Golay码的编码和解码原理,理论分析了采用脉冲编码技术对系统信噪比的提升效果。基于大气分层模型仿真生成了相干激光雷达时域回波信号。基于Golay码解码原理得到了脉冲编码系统的风速结果,仿真结果表明,时间分辨率为1s,距离分辨率为60m的情况下,使用Golay编码脉冲作为相干激光雷达的探测脉冲,在0~5.3km范围,风速误差小于3m·s^(-1)。在相同的测量时间内,相比于传统脉冲相干激光雷达,基于脉冲编码技术的相干激光雷达将探测距离提高了2.5km,提高了远场弱信号的信噪比。

Aiming at the low signal-to-noise ratio（RSN）and difficult extraction of coherent lidar echo signal in the far field,we propose pulse coding technology to improve the RSNand dynamic range of the system,then we study the encoding and decoding principle of Golay code in coherent lidar system,and theoretically analyze RSN improvement of the system by using pulse coding technology.We simulate the echo signal of coherent Doppler lidar based on the atmospheric slices model,and obtain the wind velocity of the pulse coding system based on the decoding principle.The simulation results show that,when the Golay code pulse is used as the detection pulse of the coherent lidar,the wind velocity error is less than 3 m·s-1 in the range of 0-5.3 km with the distance resolution of 60 m and the time resolution of 1 s.In the same measurement time,the coherent lidar with pulse coding technique can improve the detection distance by 2.5 km compared with the traditional pulse coherent lidar,which improves the RSNof the far-field weak signal.