光纤脉冲相干激光测风雷达光学天线特性分析  

Character analysis of fiber coherent LiDAR antenna

作　　者：彭涛[1] 陈涌[1] 赵培娥[1] 陈春利 杜赛 王茜[1] 范成博 周鼎富[1] PENG Tao;CHEN Yong;ZHAO Pei’e;CHEN Chunli;DU Sai;WANG Qian;FAN Chengbo;ZHOU Dingfu(Southwest Institute of Technology and 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》2022年第4期511-515,共5页Laser Technology

摘　　要：为了提高光纤脉冲相干激光测风雷达性能,采用数学建模的方法来分析光学天线特性。利用后向传播本振原理,讨论光学天线口径对系统载噪比的影响,以及光瞳截断比对天线效率的影响;提出光学接收耦合效率的定义,研究不同大气折射率结构常数条件对耦合效率和测程的影响;通过搭建实验平台,测量不同距离门内的载噪比和频谱强度等参数,验证了仿真结果。结果表明,当远场探测距离在7km~10km范围内变化时,天线最优口径为100mm,光瞳截断比最优值为0.8;相较弱湍流情况,强湍流会使同一系统测程下降近30%。此研究为光学天线的优化设计提供了理论依据。In order to improve capability of a fiber coherent light detection and ranging(LiDAR),antenna characters were analyzed with modeling method.Based on the principle of backward propagating local light,the influence of antenna aperture on signal-to-noise ratio was discussed,and the influence of pupil truncation ratio on antenna efficiency was analyzed.The definition of coupling efficiency was proposed,and the influence of atmospheric refractive constant on d coupling efficiency and range was researched.By building experimental platform to obtain signal to noise ratio and frequency spectrum intensity in different distance gates,the simulation results were verified.The results show that when the range changes from 7km to 10km,the optimal antenna aperture and pupil truncation ratio were 100mm and 0.8,respectively.Moreover,compared with weak turbulence,strong turbulence makes range decrease by 30%for the same system.The research has important theoretical significance and practical value for optimized design of antenna.

关 键 词：激光技术 光学天线 实验分析 大气湍流 

分 类 号：TN958.98[电子电信—信号与信息处理]