Analysis of SAR Response Anisotropic Behavior Using Sub-Aperture Polarimetric Data

Conventional SAR processing techniques generally assume that targets have a stationary behavior during the SAR integration. However, SAR sensors operating at lower frequencies, like Land P-band, have a wide antenna characteristic in azimuth; i.e. during the formation of the synthetic aperture, multiple squint-angles are integrated to build the full-resolution SAR image. In this paper, a fully polarimetric sub-aperture analysis method is introduced. Using deconvolution, synthesized SAR images are decomposed into subaperture data sets, which correspond to the scene responses under different azimuthal look-angles. A statistical analysis of the polarimetric parameters permits to clearly discriminate media showing a non-stationary behavior during the SAR integration. Finally, a method is proposed, which eliminates the influence of azimuthal backscattering variations in conventional polarimetric SAR data analysis.