Generation and Validation of Digital Elevation Model Using RISAT-1 SAR Interferometry

Abstract

SAR Interferometry is one of the techniques used for generating three-dimensional information about the Earth’s surface, which converts the absolute interferometric phase data of complex radar signal into topographic information. The prime objective of the study was to explore the potential of the RISAT-1 data for interferometric analysis. In this study, an attempt has made to generate the DEM of the part of Bharatpur region, Rajasthan using InSAR techniques using FFT based instead of the conventional approach due to non-availability of precise orbits. The analysis was carried out using FRS-1 data of 3 m resolution and 25 km swath corresponding to 21 February 2015 and 18 March 2015 having temporal separation of 25 days. The accuracy assessment of the generated DEM was compared with the extracted reference elevation information over 53 points from the Cartosat-1 DEM. The accuracy of the Generated DEM observed as 11.8 m and mean error of 2.3 m.