基于后向散射增强效应的双望远镜大气湍流激光雷达  

Double-Telescope Atmospheric Turbulence Lidar System Based on Backscattering Enhancement Effect

作　　者：李仕春[1] 王宇轩 宋程 宋跃辉[1] 高飞[1] 华灯鑫[1] 辛文辉[1] Li Shichun;Wang Yuxuan;Song Cheng;Song Yuehui;Gao Fei;Hua Dengxin;Xin Wenhui(School of Mechanical and Precision Instrument Engineering,Xi’an University of Technology,Xi’an 710048,Shaanxi,China)

机构地区：[1]西安理工大学机械与精密仪器工程学院,陕西西安710048

出　　处：《光学学报》2024年第24期99-104,共6页Acta Optica Sinica

基　　金：国家自然科学基金(42375134)。

摘　　要：基于激光在湍流大气中传输的后向散射增强效应,提出探测大气湍流强度的双望远镜硬目标反射激光雷达。该激光雷达系统包含一个发射通道和两个接收通道,其中一个接收通道与发射通道重合,而另一个接收通道与发射通道平行且横向偏移15 cm。基于同轴与离轴接收通道回波信号的功率比,表征接收望远镜处硬目标反射信号的后向散射增强系数与大气湍流强度之间的关系。开展静稳天气且湍流强度均匀情况下的初步观测实验,实验数据表明:当利用光束中心与加热器距离变化模拟湍流强度变化时,随着两者间距离减小,湍流强度增强,激光雷达的后向散射增强系数也单调增加;而在相同观测条件下,随着积分路径增加,后向散射增强系数单调增加并表现出饱和趋势。同时分析夜间温度和风速变化与后向散射增强系数的相关性:夜间地面温度的逐步下降趋势与常规湍流强度下降趋势基本一致,表现出较好的相关性,Pearson相关系数R为0.95;而风速的随机性不同于常规湍流强度下降趋势,其相关性较差,Pearson相关系数R为0.67。双望远镜硬目标反射激光雷达可为大气湍流探测提供有效手段。Objective Lidar remote sensing technology possesses significant advantages in detecting atmospheric parameters(such as clouds and aerosols,temperature,and wind speed)with high precision and high timeliness.However,atmospheric turbulence can affect the transmission characteristics of laser in the atmosphere,causing a series of turbulence effects such as light intensity fluctuations,phase fluctuations,beam wander,and beam spread.Based on the backscattering enhancement effect of laser transmission in turbulent atmosphere,a doubletelescope hardtarget reflection lidar system for detecting atmospheric turbulence intensity is proposed.The system realizes the measurement of backscattering enhancement coefficient by receiving the diffuse reflection echo signals of hardtarget with the double telescope.The biggest advantage of this system is the utilization of smallaperture doubletelescope receiving channels,greatly simplifying the complexity of the system and reducing equipment costs.Methods The application of doubletelescope lidar technology based on backscattering enhancement effect in atmospheric turbulence detection is studied.First,a doubletelescope hardtarget reflection lidar for detecting atmospheric turbulence intensity is proposed and designed based on the backscattering enhancement effect.The system consists of one transmission channel and two receiving channels,where one receiving channel aligns with the transmitting channel and the other is offset by 15 cm.Then,the backscattering enhancement coefficient of hardtarget reflected signal at the receiving telescope is established based on the generalized HuygensFresnel principle.Finally,the experimental system is constructed,and the preliminary experiments are conducted in calm weather with uniform turbulence intensity.The effects of turbulence intensity,laser transmission distance,temperature,and wind speed on the backscattering enhancement coefficient are studied.Results and Discussions The detection principle of the proposed backscattering enhancement effect lida

关 键 词：大气光学 激光雷达 大气湍流 后向散射增强效应 相关性分析 

分 类 号：O436[机械工程—光学工程]