Cluster Zone-Based Extended Scattering Power Components for Dual-Pol SAR Data

Target characterization parameters are crucial for accurately capturing the physical and geometric properties of land cover targets. While numerous methods and descriptors have been proposed for full-polarimetric (full-pol) SAR data to enable detailed target characterization, dual-polarimetric (dual-pol) synthetic aperture radar (SAR)-based analyses have traditionally relied on backscatter intensities and conventional dual-pol descriptors. However, these conventional descriptors lack discrimination between elementary targets, such as trihedral (or surface) and dihedral scatterers, leading to ambiguities in characterizing diverse land cover targets. Recent studies introduced advanced dual-pol descriptors that effectively characterize 'dihedral-like' and 'surface-like' scattering behaviors in dual-pol SAR data. In particular, a dual-pol target characteristic parameter, α(S), was proposed and subsequently used to derive the dual-pol three-component scattering powers, decomposing the total power into relatively coarse scattering components. Further developments, combined α(S) with wave entropy, Hw, to partition the Hw-α(S) plane into eight cluster zones, each representing specific scattering characteristics. This study proposes a zone-based scattering power (ZBP) components that exploit the centroids and areas of the cluster zones together with a metric associated with the target's position in the Hw-α(S) plane to derive extended scattering power components from dual-pol SAR data. The proposed framework decomposes the total power into finer scattering components. Assessment over diverse land cover targets demonstrates that the proposed ZBP components capture subtle variations in target scattering behavior and provide additional discriminatory information for enhanced target characterization.