中国激光, 2017, 44 (9): 0910003, 网络出版: 2017-09-07
星地同步观测数据的地基激光雷达几何因子反演方法 下载: 775次
Geometric Form Factor Retrieval Method for Ground-Based Lidar Based on Ground-Based and Space-Borne Synchronous Observation Data
遥感 激光雷达 几何因子 弹性散射激光雷达 星载激光雷达 remote sensing lidar geometric form factor elastic scattering lidar cloud aerosol lidar infrared pathfinder satellite
摘要
为了有效确定地基激光雷达系统的几何因子, 修正地基激光雷达信号接收过渡区内的回波信号, 提出了一种反演几何因子的新方法。利用星载激光雷达(CALIPSO)可以覆盖地基激光雷达探测过渡区的特点, 结合星载与地基激光雷达同步获取的回波信号, 分别反演了离轴和同轴模式下的几何因子, 并同成熟的拉曼-米氏几何因子反演方法, 以及Su Jia的联合测量法作对比。在几何因子过渡区内, 校正后的气溶胶后向散射系数与Su Jia的方法相比, 离轴和同轴模式下的平均相对误差分别提高了25.4%和10.4%。该方法克服了弹性散射激光雷达水平测量法中因大气均匀假设导致的几何因子测量结果的不确定性, 更适用于应用广泛的弹性散射激光雷达, 且可以利用CALIPSO每月过境时间稳定的特点, 对系统几何因子进行常规标定。
Abstract
To effectively retrieve the geometric form factor of the ground-based lidar and to modify the echoed signal in transition region, a new geometric form factor retrieval method is proposed. The method takes advantage of the characteristic of space-borne lidar (Cloud Aerosol Lidar Infrared Pathfinder Satellite Observation, CALIPSO) that it can cover the detection transition area of the ground-based lidar. The geometric form factors in off-axial and coaxial modes are determined by the use of simultaneous lidar measurement data from the space-borne lidar and the ground-based lidar. The results are compared to the results of comprehensive Raman-Mie method and Su Jia′s method. In the transition region of the geometric form factor, the average relative errors of the aerosol backscatter coefficient can be improved by 25.4% and 10.4% compared to those of Su Jia′s method in off-axial and coaxial modes, respectively. This method overcomes the uncertainties caused by assumptive uniformity of the atmosphere in the horizontal measurement method of the elastic scattering lidar. It is more suitable for the widely-used elastic scattering lidar. The geometric form factor of the ground-based lidar can be routinely calibrated by use of the regular transit time of CALIPSO with stable features.
齐白玉, 陈思颖, 张寅超, 陈和, 郭磐. 星地同步观测数据的地基激光雷达几何因子反演方法[J]. 中国激光, 2017, 44(9): 0910003. Qi Baiyu, Chen Siying, Zhang Yinchao, Chen He, Guo Pan. Geometric Form Factor Retrieval Method for Ground-Based Lidar Based on Ground-Based and Space-Borne Synchronous Observation Data[J]. Chinese Journal of Lasers, 2017, 44(9): 0910003.