利用L波段星载重复轨道干涉SAR提取DEM及大气效应分析

以四川省茂县、安县地区的ALOS PALSAR L波段雷达影像为数据源,在对地形复杂区的配准、解缠等算法研究的基础上,结合SAR特有的成像几何结构,对两幅SAR图像进行快速自动配准,配准误差小于0.2个像元;在去除平地引起的干涉相位变化后,运用MCF对缠绕相位进行解缠,在此基础上提取研究区的数字高程模型(DEM),分析发现精度受多种因素影响,其中波长较长的L波段数据比波长较短的时间相关性好,此外为消除大气效应,采用改进的相位累积法去除大气的影响,在一定程度上提高DEM精度。其误差范围在±10m左右,对快速提取地形信息具有一定的借鉴意义。

Using repeat orbit L-band interferometric SAR to extract DEM and analyzing the atmospheric effects

This paper,taking ALOS PALSAR L-band radar images as the data source in the counties of Maoxian and Anxian,Sichuan Province,adopts a coherent coefficient method aiming at two SAR images automatic registration and MCF algorithm at phase unwrapping based on the research of registration, unwrapping algorithms,extracted study area's Digital Elevation Model(DEM).The key technology of interferometric synthetic aperture radar is focused on the basis of the analysis of the current research status.At the time of interferometry,the SAR data with longer wavelength L-band has better temporal coherence than the shorter wavelength.Then the accuracy and characteristics of DEM data are analyzed, w hose most error range is about ± 10 m,and the influence of atmospheric effects in interferometriv aperture radar topographic map is discussed,which can provide the basic data for the research work of subsequent surface deformation.