激光测高卫星大气散射延迟改正现状及展望

Abstract

Laser altimetry satellite can obtain the surface elevation information of sub-meter or even centimeter-level in a wide range, but it is inevitably affected by the scattering caused by particles such as clouds and aerosols. The laser ranging and final height measurement errors caused by forward scattering of the cloud or fog can not be ignored. In this paper, the atmospheric scattering error correction technology of laser altimetry satellite was systematically reviewed, and the satellite laser altimeter system parameters, atmospheric detection and scattering correction algorithm at home and abroad were introduced. Different from the Monte Carlo simulation correction method theory, an atmospheric scattering correction algorithm based on exponential function model was proposed. The data of GLAS (Geo-science Laser Altimeter System) on the ICESat (Ice, Cloud and land Elevation Satellite) in Qinghai Lake and other regions was selected for the experiment, and the experimental results show that the algorithm can effectively improve the accuracy of the altimetry data affected by atmospheric scattering when the optical thickness is less than 2, and the data availability rate can be improved by about 9%. The algorithm is easier to realize operation application. Finally, according to the necessity of synchronous detection of atmospheric parameters, some suggestions for atmospheric scattering correction of domestic laser altimetry satellites were put forward in combination with onboard atmospheric parameter detection equipment.