Polarimetric 3-D reconstruction from multicirular SAR at P-band

Abstract

Three-dimensional reconstruction and sub-wavelength resolution can be achieved in Circular SAR (CSAR) mode with a single pass. However, circles or arcs are present when the assumed height during focussing is not that of the target. In 3-D imaging these artifacts are seen as cone-shaped sidelobes due to the poor resolution in the direction perpendicular to the line of sight. In this work, a multicircular fully polarimetric SAR experiment using DLR’s F-SAR system at P-band is presented. The purpose is to enhance the resolution while focusing 3-D images by retrieving the backscattering profile in elevation. A phase calibration method using the Singular Value Decomposition (SVD) is presented. Processing methods such as Fast Factorized Back Projection for circular tracks, and reconstruction techniques with coherent averaging with beamforming and compressive sensing for 3-D are used. Finally, the first holographic SAR tomogram at P-Band of a forested area is presented.