Processing Techniques for Repeat Pass ScanSAR Interferometry

Abstract

ScanSAR interferometry is an attractive option for ef-ficient topographic mapping of large areas and for monitoring of large scale motions. Only ScanSAR interferometry has made it possible to map almost the entire landmass of the earth in a single SRTM mission. The operational satellite RADARSAT as well as future systems like ENVISAT offer ScanSAR imaging modes. This paper describes how this mode can be exploited for repeat-pass interferometry. The paper provides a practical tour to RADARSAT ScanSAR interferometry. Problems addressed are azimuth scanning pattern synchronization, spectral shift filtering in the presence of high squint, phase preserving ScanSAR processing, ScanSAR interferogram formation, and beam alignment. The first RADARSAT ScanSAR DEM is presented.