Local co-registration for distortion reduction in SAR interferogram using amplitude information - combination of SPEC method and shape-from-shading -

Abstract

Correcting the phase ambiguity of synthetic aperture radar (SAR) interferogram is an important process to create an accurate digital elevation model (DEM) for analyzing the geometry. The ambiguity often appears as the rotational point in the phase map which are called singular points (SPs). One of the origins of the SPs is the local distortion of the master and the slave, the source of interferogram. To solve this problem, we previously proposed a local co-registration method which employs the SPs as the evaluation criterion(SPEC method). In this paper, we propose an improved version of this co registration method. This version refers the amplitude in formation for shape-from-shading technique, which estimates the divergence of the range direction. We demonstrate the effectiveness of the improvement by comparing the DEMs generated from those interferograms.