Non-negative scattering power decomposition for PolSAR data interpretation
This study presents a hybrid technique for polarimetric synthetic aperture radar (PolSAR) data decomposition. The proposed technique aims to overcome the negative power problem of model-based decomposition methods. To achieve this, matrix rotation theory is used along with hybrid scattering models. The matrix rotation theory is utilised on the basis of underlying dominant scatterer to remove maximal of the cross-polarisation power generated by the coupling between orthogonal states of polarisation. Removing the coupling energy between orthogonal states not only optimised the PolSAR coherency matrix but also transform it more close to reflection symmetry condition. The applicability of the proposed approach is shown through the implementation of hybrid three- and four-component decomposition methods. The proposed hybrid methods are experimentally verified on C-band Radarsat-2 San Francisco and L-band UAVSAR Hayward datasets. For further analysis, different land-cover patches are selected. Moreover, the variations in percentage of negative power pixels are investigated by employing different volume scattering models. Comparative analyses are presented with existing PolSAR decomposition techniques in terms of normalised scattering power means and amount of negative power pixels. All experimental analyses clearly report the superiority of the proposed hybrid approach through improvements over existing PolSAR decomposition techniques along with non-negative scattering powers.
