高光学效率相干多普勒激光雷达的测风性能分析与测试

Analyzing and testing of performances of high optical efficiency CDL in wind sensing

近期研发了一套高光学效率全光纤化相干激光雷达设备,可用于风场的实时探测。该相干激光雷达工作于1.55μm波段,望远镜直径50 mm,时间分辨率和距离分辨率分别是1 s和30 m。系统集成了光纤结构的接收单元、可编程扫描模式的两轴扫描头及一个用于实时信号处理的多核数字信号处理器。对系统的测风性能进行了理论分析并同实验结果进行了对比,验证了系统测量距离达到5 km。之后,通过将激光雷达与超声波风速仪数据进行对比验证系统的测量精度。经过数据分析水平风速相关系数达0.980,标准差为0.235 m/s,风向数据相关系数达0.993,标准差为3.105°。表明该相干激光雷达具有优良的性能,可以应用于大气边界层内的风场探测。

Recently a high optical efficiency all-fiber coherent Doppler lidar(CDL)system was developed to achieve real-time measurements of wind fields.The coherent lidar worked on 1.55μm band,the diameter of the felescope was 50 mm,the temporal and spatial resolution were 1 s and 30 m respectively.In addition,the system consisted of a fiber-based optical transceiver unit,a 2-axis scanner which can program scanning scheme,and a multicore digital signal processor(DSP)for real-time signal processing.Theoretical performances of the system in wind sensing were estimated and compared with experimental results,it verified that the measurement range was 5 km.In comparative experiment,the system and ultrasonic anemometer measured wind field simultaneously.Measured data were compared and analyzed,the result were listed as follow:correlation coefficient of wind speed was 0.980 and standard deviation was 0.235 m/s;correlation coefficient of wind direction was 0.993 and standard deviation was3.105°.The results prove that the system has excellent performance,can be widely used for wind detection in atomospheric boundary layer.