Urban Tomographic Imaging Using Polarimetric SAR Data

Abstract:
SAR Tomographic techniques provide scene reflectivity estimation along azimuth, range, and elevation coordinates and are used for separating the contribution of multiple coherent scatterers lying in the same range azimuth resolution cell. Tomographic reconstruction along elevation is achieved by using stacks of images of the same scene acquired with slightly different view angles. Due to the limited number of the available data and to the uneven spacing between acquisition trajectories, the obtained reconstructions suffers from the problem of outliers and high level sidelobes, which produce a large number of false scatterers detection. To solve this problem, statistical tests for the detection of multiple scatterers with a constant false-alarm rate have been introduced for the case of single-polarization data of urban areas. In this paper, the introduction of a specific detector for urban scenarios that exploits polarimetric data is addressed. The detector is based on a polarimetric model that takes into account the scattering mechanisms encountered in urban applications and has the aim of improving the separation of multiple scatterers respect to the single polarization case. The proposed approach will be validated on dual polarimetric SAR real data.