Development of a Meteorological Lidar for the Analysis of Atmospheric Dynamical Behavior

本研究的目的是开发一套实用的气象激光雷达或激光雷达系统，用于远程测量对流层的风、温度和湿度等主要气象参数。该系统可用于分析大气环境问题的基本动力学特性。研制了一种结构紧凑、重量轻的激光雷达作为遥感大气系统，并进行了实际应用试验。(1)人眼安全的风、温、湿传感多功能激光雷达系统的研制。波长355nm，平均功率0.6 W的紫外单频激光器使用直径20 cm的望远镜和光子计数探测器。在直接探测多普勒激光雷达方案中，采用了高分辨率的法布里-珀罗标准子滤波。温度传感基于双通道光栅滤波器的旋转拉曼散射方案，湿度传感基于单通道光栅滤波器的振动拉曼散射方案。这些主要气象参数的空间剖面图可以同时测量。最终测试风速测量精度为1.5 m/s， 1.5 km范围内温度测量精度为1K， 2 km范围内湿度测量精度为10%。(2)采用ld泵浦单频调q Nd: YAG激光器的紧凑型多普勒激光雷达的研制。研制了一种紧凑的ld泵浦调q固态Nd: YAG激光器。单频振荡采用注入播种和行波腔技术。采用稳频技术，在10khz脉冲重复频率下，3W平均功率下脉冲频率稳定度为0.23 MHz。利用直径20 cm的扫描式望远镜测量532 nm处的二次谐波光束。风速测量可以在3 km范围内进行，精度为0.6 m/s。

The purpose of this research is to develop a practical meteorological lidar or laser radar system for remotely measuring major meteorological parameters of wind, temperature and humidity in the troposphere. The system is useful for analyzing fundamental dynamical properties of the atmospheric environmental issues. A compact and light-weight lidar has been developed and tested for practical application as the remote atmospheric sensing system.(1) Development of eye-safe multi-function lidar system for wind, temperature and humidity sensing. The UV single frequency laser at 355 nm with 0.6 W average power was used with a 20-cm diameter telescope and a photon counting detectors. For the wind measurement, a high-resolution filter of the Fabry-Perot etalon was employed in the direct detection Doppler lidar scheme. The temperature sensing is based on the rotational Raman scattering scheme using two-channel grating filters and the humidity is on the vibrational Raman scattering scheme using a single grating filter. The spatial profiles of these major meteorological parameters could be measured simultaneously. The accuracy of the wind measurements was finally tested to be 1.5 m/s at 3 km range, temperature accuracy was 1K at 1.5 km range and humidity was 10% at 2 km range.(2) Development of a compact Doppler lidar with a LD-pumped single-frequency, Q-switched Nd : YAG laser. A LD-pumped compact Q-switched solid-state Nd : YAG laser has been developed. The injection seeding and the traveling wave cavity technique was employed for the single frequency oscillation. Frequency stabilization technique was applied and the pulse frequency stability was 0.23 MHz for 3W average power at 10-kHz pulse repetition frequency. The second harmonic beam at 532 nm was used for the wind measurement using a scanning 20 cm diameter telescope. The wind measurement was possible at the range of 3 km with theaccuracy of 0.6 m/s.