Beyond TomoSAR vertical reflectivity profiles in forest scenarios: Ground polarimetric covariance estimation at multiple frequencies

The purpose of this paper is to investigate how SAR Tomography (TomoSAR) can be used to estimate ground polarimetric covariances in forest scenarios in order to increase the amount of information that can be extracted from SAR data stacks is beyond the vertical reflectivity profiles. Under the hypothesis of a two-layer model composed by ground and volume contributions, an algorithm is proposed that makes use of an a priori knowledge of the ground height. The performance in the estimation of the ground polarimetry is investigated with respect to frequency and accuracy of the ground height estimated from the TomoSAR stack. This analysis is carried out by processing an L- and a P-band TomoSAR data stacks acquired by the DLR's E-SAR sensor over the temperate forest of Traunstein.