AN EFFICIENT APPLICATION OF POLARIMETRIC SAR DATA FOR PARAMETER RETRIEVAL

Abstract

The main aim of this dissertation is to develop a modeling approach for retrieval of soil moisture using Optical data and fully Polarimetric Synthetic Aperture Radar (PolSAR) data. The presence of vegetation cover is the key problem to estimate soil moisture. Most of the techniques for retrieval of soil moisture have been developed for bare soil using active microwave remote sensing. The vegetation provides multiple scattering effects so these techniques could not be used directly for vegetated terrains. In this approach, we have used Optical data to parameterize the vegetation. This method aims to combine the information from LANDSAT 8 (Land Satellite) data and PALSAR-2 (Phased Array type L-band Synthetic Aperture Radar) data to develop an algorithm for retrieval of soil moisture. We obtain soil moisture in the presence of agricultural vegetation by means of Polarimetric SAR images and Leaf area index (LAI). A look-up table (LUT) is constructed in order to obtain the dielectric constant of soil. The dielectric constant obtained varies from 4.73 to 25. The results obtained shows the volumetric moisture content varying from 7% to 40%. The Root mean square error (RMSE) obtained is fairly small considering the effects of vegetation