拉曼-米激光雷达测温通道残余几何因子修正

拉曼-米激光雷达高低阶拉曼通道的几何因子因不同通道光学器件和探测器的性能差异并非完全一致，会引入近地面温度测量误差，针对这一问题，提出一种修正测温通道残余几何因子的方法. 该方法首先通过探空温度和标定的归一化光谱透过率计算得到高低阶拉曼信号的有效微分散射截面之比，然后从拉曼信号比值中求解出残余几何因子廓线. 利用北京理工大学激光雷达实验室研制的转动拉曼-米激光雷达系统的探测数据，实验验证了该方法的有效性. 结果表明，该方法能较好地修正残余几何因子对温度探测的影响，显著提高近地面1.5 km探测高度内温度反演精度，有助于提高拉曼-米激光雷达对边界层大气的探测能力. 

Correction of Residual Overlap for Temperature Measurements from Raman-Mie Lidar

The overlap functions of high- and low-order channels from Raman-Mie lidar are different due to the influence of optical devices and detectors in each channel, which will cause errors in temperature measurement near the ground. In order to solve this problem, a new method to correct the residual overlap of the temperature measurement channel was proposed. This method firstly calculated the ratio of the effective differential scattering cross section of the high- and low-quantum number Raman signals through the radiosonde temperature and the calibrated normalized spectral transmittance, and then the residual overlap profile was calibrated by the Raman signal intensity ratio. The effectiveness of this method was verified by the experimental data of Raman-Mie lidar. The results show that the effect of overlap on temperature retrievals can be exactly corrected using the new method, and can significantly improve the accuracy of temperature inversion near the ground, and enhance the detecting performance of pure rotational Raman-Mie lidar in the boundary layer.