Fusion of polarimetric channel information of PALSAR data for land cover classification

Abstract

Fully polarimetric radars are capable of preserving detailed information about the targets because of the amplitude and phase information they contain which helps in distinguishing different scattering mechanisms. Therefore, nowadays it is needed to use this information for various applications, i.e., classification, target identification etc. In polarimetry, circular (L: left-hand circular polarization and R: right-hand circular polarization) as well as linear (H: horizontal polarization and V: vertical polarization) polarizations have their own advantages. In this paper, an attempt has been made to highlight the effect and importance of both types of polarizations for land-cover classification using ALOS (Advanced Land Observing Satellite) PALSAR (Phased Array-type L-band Synthetic Aperture Radar) quad-polarimetric data. Polarization responses from certain targets in linear (i.e., HH, HV, VV) and circular (i.e., LL, LR, RR) bases have been extensively analysed. Supervised classification using minimum distance classifier is used to examine the performance of both the polarization bases for terrain classification. It has been observed that circular basis polarization may be suitable for better estimation of water class unlike linear basis polarization and inclusion of circular basis enhances the classification results. This type of study will be quite helpful in the near future to enhance the special features of terrain covers.