空气温度绝对探测激光雷达系统标定技术

Calibration Technology of Lidar System for Air Temperature Absolute Detection

为了解决接触式空气温度探测易受太阳辐射和地面辐射影响的问题,实现空气温度的绝对测量,提出基于Fabry-Perot干涉仪扫描散射谱进而反演温度的高光谱分辨率激光雷达遥感探测方法。系统参数标定是影响温度探测精度的重要因素。利用连续激光器对扫描Fabry-Perot干涉仪的驱动电压、半峰全宽、自由光谱范围、温度控制精度等参数进行了标定。通过标定实验,得到10 GHz的频率扫描范围对应的电压幅值为3.48 V;Fabry-Perot腔0.1℃的温度变化对应0.21 GHz的频率漂移。利用可控制温度和压力的散射池对激光雷达温度探测系统进行了标定,经系统误差校正后,反演温度与设置温度获得了较好的一致性,这为实际温度精确探测和反演提供了基础。

In terms of the disadvantage that contact air temperature detection is vulnerable to solar radiation and ground radiation,a remote sensing detection method of high spectral resolution lidar is proposed,and it is based on the Fabry-Perot interferometer which scans the scattering spectrum and conducts temperature retrieval,so as to realize the absolute measurement of air temperature.System parameter calibration is an important factor affecting the accuracy of temperature detection.Parameters such as driving voltage,full width at half maximum,free spectral range,and temperature control accuracy of the Fabry-Perot interferometer are calibrated by continuous laser.Through the calibration experiment,the corresponding voltage amplitude is 3.48 V at a frequency scanning range of 10 GHz;a temperature change of 0.1℃at the Fabry-Perot cavity corresponds to the frequency drift of 0.21 GHz.The lidar temperature detection system is calibrated by using the scattering cell which can control the temperature and pressure.After the systematic error correction,the retrieval temperature is in good agreement with the preset temperature,which lays a foundation for accurate detection and retrieval of the actual temperature.