Two-sided Long Baseline Radargrammetry from Ascending Descending Orbits with Application to Mapping Post-seismic Topography in the West Sichuan Foreland Basin  

作　　者：CHENG Hai-qin CHEN Qiang LIU Guo-xiang YANG Ying-hui LIU Li-yao 

机构地区：[1]Department of Remote Sensing and Geoinformation Engineering, Southwest Jiaotong University [2]School of Civil Engineering and Architecture, East China Jiaotong University

出　　处：《Journal of Mountain Science》2014年第5期1298-1307,共10页山地科学学报（英文）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.41472255,51178404);Open Research Fund by Sichuan Engineering Research Center for Emergency Mapping & Disaster Reduction(Program K2014B006);Fundamental Research Funds for the Central Universities(Grant Nos.SWJTU12ZT07,2682014BR014)

摘　　要：One-sided ascending or descending Synthetic Aperture Radar（SAR） stereoradargrammetry has limited accuracy of topographic mapping due to the short spatial baseline（-100 km） and small intersection angle. In order to improve the performance and reliability of generating digital elevation model（DEM） from spaceborne SAR radargrammetry, an exploration of two-sided stereoradargrammetry from the combination of ascending and descending orbits with geometric configuration of long spatial baseline（-1000 km） was conducted in this study. The slant-range geometry between SAR sensors to the earth surface and the Doppler positioning equations were employed to establish the stereoscopic intersection model. The measurement uncertainty of two-sided radargrammetric elevation was estimated on the basis of radar parallax of homogeneous points between input SAR images. Two stereo-pairs of ALOS/PALSAR（Advanced Land Observing Satellite/Phased Array type L-band Synthetic Aperture Radar） acquisitions with the orbital separation almost 1080 km over the west Sichuan foreland basin with rolling topography in southwestern China were employed in the study to obtain the up-to-date terrain data after the 2008 Wenchuan earthquake that hit this area. Thequantitative accuracy assessment of two-sided radargrammetric DEM was performed with reference to field GPS observations. The experimental results show that the elevation accuracy reaches 5.5 m without ground control points（GCPs） used, and the accuracy is further improved to 1.5 m with only one GPS GCP used as the least constraint. The theoretical analysis and testing results demonstrate that the twosided long baseline SAR radargrammetry from the ascending and descending orbits can be a very promising technical alternative for large-area and high accuracy topographic mapping.

关 键 词：Ascending and descending orbits Twosided SAR radargrammetry Long baseline Image parallax Accuracy assessment 

分 类 号：P225.1[天文地球—大地测量学与测量工程]