Seven-Component Decomposition Using Refined Volume Scattering Models and New Configurations of Mixed Dipoles

Abstract

In this paper, an extended seven-component decomposition method using refined volume scattering models and new configurations of mixed dipoles (M7SD) is proposed to interpret the scattering mechanisms of various terrain types. In the M7SD, refined volume scattering models are proposed to reasonably characterize the scattering mechanisms of various land covers with different orientation angles, and the redefined configurations of the mixed dipoles, which have better explanations for the scattering mechanisms, are introduced. Although the diameter of the dipole used in the experiment is very small, the superposition of two dipoles in the same plane will cause one of the dipoles to have a distance from the plane. According to the experimental results, since the distance between one of the dipoles and plane cannot be ignored, it will cause an error between the scattering matrix obtained by the experiment and the scattering matrix obtained under ideal conditions. In this case, in the M7SD, two dipoles are placed in two planes, respectively, with a distance of half wavelength. The performance of the proposed method is demonstrated and evaluated with the spaceborne C-band GaoFen-3, Radarsat-2 and airborne Lband ESAR fully polarimetric data over different study sites. The experimental results demonstrate that the use of M7SD can reasonably interpret the scattering mechanisms of various terrain types (especially the building areas with large orientation angles), overcome the overestimation of the volume scattering and reduce the percentage of negative scattering power pixels.

An Adaptive Polarimetric Target Decomposition Algorithm Based on the Anisotropic Degree

“…Meanwhile, Hu et al [32] described buildings at different azimuthal angles and distinguished built-up and natural areas by using the rotated dihedral model. The refined volume scattering model proposed by Wang et al [33] can rationally explain the scattering mechanisms of various terrain types (especially built-up areas with large azimuths), overcome the overestimation of volume scattering, and reduce the percentage of negatively scattered power pixels. For the forest region, they also introduced a new model to distinguish artificial structures with compensated directional angles and natural media [34], combining the dihedral corner reflector scattering model and the polarimetric orientation angle (POA) to better separate the forest from the buildings [35].…”