Performance Analysis of Flat Surface Assumption and Residual Motion Errors on Airborne Repeat-pass InSAR
Lin Xue①②③ Li Fang-fang①②③ Hu Dong-hui①② Ding Chi-biao①②
①(Key Laboratory of Technology in Geo-spatial Information Processing and Application System, Chinese Academy of Sciences, Beijing 100190, China) ②(Institute of Electronics, Chinese Academy of Sciences, Beijing 100190, China) ③(University of Chinese Academy of Sciences, Beijing 100190, China)
Abstract：When applying to the airborne repeat-pass Interferometric Synthetic Aperture Radar (InSAR), which has long synthetic aperture and large azimuth-dependent errors, the surface assumption used to simply the time-domain algorithm model and the residual motion errors due to the precision of the navigation system will affect the imaging result and the interferometric measurement. This paper analyzes the altitude errors introduced by the surface assumption and the residual motion errors due to the precision of the navigation system. We deduce the range errors model during the single pass and analyze the effects of these errors on the plane location, interferometric phase and DEM precision. Then the accuracy of the theoretical deduction is verified by simulation and real data. The research provides theoretical bases for the system design and signal processing of airborne repeat-pass InSAR.
