米散射多普勒激光雷达性能改进

介绍了自行研制的米散射多普勒激光雷达的系统结构。针对系统存在的问题,对接收机子系统、工作时序、扫描方式等方面作了改造。实验结果表明:改造后系统光学鉴频器的频谱稳定性提高了2.8倍;消除了系统近距离的探测盲区;在0~2.5 km的高度范围内,当垂直距离分辨力为21.2 m、脉冲累积数为9 000发时,改造后的米散射多普勒激光雷达系统连续30 min测量的水平风速大小和方向的标准偏差的最大值分别小于1 m/s和18.3°,平均值分别小于0.43 m/s和7.7°;与探空仪的风场对比测量结果吻合得很好;当每个径向脉冲累积数为1 000发时,采用四波束扫描获得的2 km以下东西方向径向风速的相关系数为0.99,偏差为-0.038 m/s,标准偏差为1.34 m/s。

Performance improvement of Mie Doppler lidar

The structure of a self-developed Mie Doppler lidar system is introduced. Aiming at the problems existing in the former system, the receiver sub-system, working time series, and scanning mode etc. were upgraded. Experimental results show that the spectrum stability of optical discriminator is improved by 2.8 times. The blind range of detection is eliminated. With 9 000 laser shot integration and 21.2 m vertical resolution, the averaged standard deviation of horizontal wind speed and direction over the altitude from 0 to 2.5 km for three consecutive 10 min measured by the modified Mie Doppler lidar are below 0.43 m/s and 7.7° with the maximum values of 1 m/s and 18.3°, respectively. Comparisons of lidar and wiresonde wind observations show good agreement. With 1 000 laser shot integration