ASSESSMENT OF L-BAND SAR DATA AT DIFFERENT POLARIZATION COMBINATIONS FOR CROP AND OTHER LANDUSE CLASSIFICATION

Abstract

In the present study evaluation of L-band SAR data at difierent polarization combinations in linear, circular as well as hybrid polarimetric imaging modes for crop and other landuse classiflcations has been carried out. Full-polarimetric radar data contains all the scattering information for any arbitrary polarization state, hence data of any combination of transmit and receive polarizations can be synthesized, mathematically from full-polarimetric data. Circular and various modes of hybrid polarimetric data (where the transmitter polarization is either circular or orientated at 45 - , called …=4 and the receivers are at horizontal and vertical polarizations with respect to the radar line of sight) were synthesized (simulated) from ALOS- PALSAR fullpolarimetric data of 14th December 2008 over central state farm central latitude and longitude 29 - 15 0 N/75 - 43 0 E and bounds for northwest corner is 29 - 24 0 N/75 - 37 0 E and southeast corner is 29 - 07 0 N/75 - 48 0 E in Hisar, Haryana (India) Supervised classiflcation was conducted for crops and few other landuse classes based on ground truth measurements using maximum-likelihood distance measures derived from the complex Wishart distribution of SAR data at various polarization combinations. It has been observed that linear full- polarimetric data showed maximum classiflcation accuracy (92%) followed by circular-full (89%) and circular-dual polarimetric data (87%), which was followed by hybrid polarimetric data (73{75%) and then linear dual polarimetric data (63{71%). Among the linear dual polarimetric data, co-polarization complex data showed better