光纤Mach-Zehnder干涉仪测风激光雷达技术与数值仿真  

Numerical Simulation for Wind Lidar Based on Optical Fiber Mach-Zehnder Interferometer

作　　者：谭林秋[1] 华灯鑫[1] 汪丽[1] 何廷尧[1] 常博[1] 

机构地区：[1]西安理工大学机械与精密仪器工程学院,西安710048

出　　处：《光子学报》2015年第7期113-119,共7页Acta Photonica Sinica

基　　金：国家自然科学基金(Nos.61205189;61275185)资助

摘　　要：基于光纤Mach-Zehnder干涉仪双边缘检测技术,提出并设计了一套全光纤非相干测风激光雷达系统,对多普勒频移的提取和风速反演算法进行了理论分析,针对大气分子散射信号的特点,对光纤Mach-Zehnder鉴频系统进行了优化设计.应用美国标准大气模型,对系统的灵敏度、信噪比以及测量误差进行了数值仿真.仿真结果表明,对532nm波长的地基分子散射测风激光雷达,当垂直距离分辨率为300m,进行1 000次激光脉冲累计平均后,得到径向探测距离达到20km,径向风速在±100m/s的范围内时,径向风速误差小于1.4m/s,说明此系统可以进行远距离大尺度风速的测量,为新型小型化测风激光雷达的开发及研制提供了一种可行的技术方案.An all-fiber incoherent wind lidar system was proposed and designed based on double-edge technique of optical fiber Mach-Zehnder interferometer. The algorithms for Doppler shift extraction and for wind velocity retrieval were theoretically analyzed. The optical fiber Mach-Zehnder interferometer used as a spectral analyzer in the proposed system, was discussed to optimize for wind velocity measurement based on the signals backscattered by the molecules. Performances including wind measurement sensitivity, signal-to-noise ratio and measurement error of lidar system were numerically simulated based on the U.S. standard atmospheric model. For a ground-based molecular wind lidar at a wavelength of 532 nm, an error in the line-of-sight velocity component of the wind was found to be smaller than 1.4 m/s up to an altitude of 20 kin, with the line-of-sight wind velocity within the range of -± 100 m/s, a 300-shot average and a vertical resolution of 1 000 m. Obtained results show that the designed system can be applied for long-distance and large-scale wind velocity measurement. The system will be able to provide a technical solution for the develooment of the comoact Doppler lidar.

关 键 词：激光雷达 多普勒测风 数值仿真 光纤Mach—Zehnder干涉仪 双边缘检测技术 风速反演 鉴频系统 

分 类 号：P412.16[天文地球—大气科学及气象学] TN958.98[电子电信—信号与信息处理]