Seven-Component Model-Based Decomposition for PolSAR Data with Sophisticated Scattering Models

Abstract

Due to incomprehensive and inaccurate scattering modeling, the state-of-the-art polarimetric synthetic aperture radar (PolSAR) model-based target decompositions are incapable of effectively depicting the scattering mechanism of obliquely oriented urban areas. In this paper, a seven-component model-based decomposition scheme is proposed by constructing several sophisticated scattering models. First, an eigenvalue-based obliquely-oriented dihedral scattering model is presented to reasonably distribute the co-polarization and cross-polarization scattering powers in obliquely oriented urban areas, thus accurately characterizing the urban scattering. Second, the ±45° oriented dipole and ±45° quarter-wave reflector scattering models are incorporated for the purpose of accounting for the real and imaginary components of the T 13 element in the coherency matrix so as to fully utilize polarimetric information. Finally, according to their mathematical forms, several strategies for model parameter solutions are designed, and the seven-component decomposition is fulfilled. Experimental results conducted on different PolSAR data demonstrate that the proposed method considerably improves the PolSAR scattering interpretation in a more physical manner compared to other existing model-based decomposition, which can be applied for urban area detection, classification, and other urban planning applications.

Improved General Polarimetric Model-Based Decomposition for Coherency Matrix

“…Thirdly, the representative volume scattering models can be adaptively selected by using the nonlinear least squares optimization method, so that the scattering mechanism of a target can fit the observations well. Finally, most model-based decomposition methods [29][30][31][32][33][34][35] usually subtract the helix scattering contribution at first, and then obtain the volume scattering contribution, or reassign the decomposed power by manual intervention. This strategy may lead to overestimation or underestimation of the power weights of the scattering components, or even negative power.…”

“…By solving the above equations, f d Re[α](θ s , θ d ).and f s Re[β * ](θ s , θ d ) can be obtained. Similarly, according to (31) and (33), the following equations can be formed.…”

“…The pioneering work of MBD is Freeman-Durden decomposition [28], which has been successfully applied to the natural distributed target areas under the well-known reflection symmetry condition. Due to the advanced methodology of MBD, a lot of improvements have been derived based on this method, such as Yamaguchi-based decomposition methods [29][30][31][32], seven-component model-based decomposition method [33], feature-driven superpixel segmentation method [34], and L 1 -regularization approach [35], etc.…”

Ship Recognition from Chaff Clouds with Sophisticated Polarimetric Decomposition

“…Therefore, to further utilize polarimetric information and to relieve the constraint of the reflection symmetry assumption, the T 13 term should be accounted for by certain scattering models in the MBD. To this end, two extra sophisticated scattering models, i.e., the ±45 • oriented dipole (OD) and ±45 • oriented quarter-wave (OQW) scattering models [21,22] are further integrated into the proposed decomposition scheme.…”

Model-Based Polarimetric Target Decomposition With Power Redistribution for Urban Areas

“…Xiang et al [22] modeled rotated dihedral corner reflectors for buildings with large oriented angles, so that cross scattering of the oriented building areas can be separated from the overall cross-polarized scattering component. Fan et al [23] proposed an oblique dihedral scattering model which expanded the 6SD into sevencomponent polarimetric decomposition. On the basis of 7SD, Malik et al [24] introduced two scattering components by combining the dipoles, and then proposed a nine-component decomposition method.…”