Liu Dong, Yang Yongying, Cheng Zhongtao, Huang Hanlu, Zhang Bo, Ling Tong, Shen Yibing
State Key Laboratory of Modern Optical Instrumentation, Zhejiang University, Hangzhou, Zhejiang 310027, China.
Opt Express. 2013 Jun 3;21(11):13084-93. doi: 10.1364/OE.21.013084.
Taking advantage of the broad spectrum of the Cabannes-Brillouin scatter from atmospheric molecules, the high spectral resolution lidar (HSRL) technique employs a narrow spectral filter to separate the aerosol and molecular scattering components in the lidar return signals and therefore can obtain the aerosol optical properties as well as the lidar ratio (i.e., the extinction-to-backscatter ratio) which is normally selected or modeled in traditional backscatter lidars. A polarized HSRL instrument, which employs an interferometric spectral filter, is under development at the Zhejiang University (ZJU), China. In this paper, the theoretical basis to retrieve the aerosol lidar ratio, depolarization ratio and extinction and backscatter coefficients, is presented. Error analyses and sensitivity studies have been carried out on the spectral transmittance characteristics of the spectral filter. The result shows that a filter that has as small aerosol transmittance (i.e., large aerosol rejection rate) and large molecular transmittance as possible is desirable. To achieve accurate retrieval, the transmittance of the spectral filter for molecular and aerosol scattering signals should be well characterized.
利用大气分子的卡巴尼斯 - 布里渊散射的宽光谱范围，高光谱分辨率激光雷达（HSRL）技术采用窄光谱滤波器来分离激光雷达回波信号中的气溶胶和分子散射分量，因此能够获得气溶胶光学特性以及激光雷达比（即消光与后向散射比），而在传统后向散射激光雷达中，该比值通常是选定的或通过建模得到的。中国浙江大学正在研制一种采用干涉光谱滤波器的偏振HSRL仪器。本文介绍了反演气溶胶激光雷达比、退偏振比以及消光和后向散射系数的理论基础。对光谱滤波器的光谱透过率特性进行了误差分析和灵敏度研究。结果表明，理想的滤波器应具有尽可能小的气溶胶透过率（即高气溶胶抑制率）和大的分子透过率。为实现精确反演，应很好地表征光谱滤波器对分子和气溶胶散射信号的透过率。
