提出了一种确定激光雷达几何重叠因子的新方法。研究了大气分子纯转动拉曼谱线强度分布特征。利用大气分子总的纯转动拉曼激光雷达信号结合瑞利米氏散射激光雷达信号能精确反演激光雷达几何因子。这种方法消除了振动拉曼方法中气溶胶波长指数影响以及水平测量法气溶胶非均匀性的限制。数值模拟结果表明：在大气温度三种分布模型和气溶胶波长指数三种分布模型下几何因子反演的最大相对误差小于0.5%。根据实际激光雷达信号反演得到了系统的几何因子。

A new method was presented to determine lidar geometric form factor. The intensity distribution charateristic of pure rotational Raman spectra at different temperature is studied. Lidar geometric form factor can be determined accurately with the sum of pure rotational Raman lidar signal and the Rayleigh-Mie lidar signal of atmospheric molecules. The method reduces aerosol wavelength exponent effect compared with vibrational Raman method and aerosol uniformity limit in contrast to horizontal determination method. The numerical simulation shows that the maximum relative error of geometric form factor retrieved from three kinds of temperature distribution modes and three kinds of aerosol wavelength exponent distribution modes is less than 0.5%. The lidar deomenic form factor is determined with real lidar aignal.