Modifications on parametric models for distributed scattering centres on surfaces with arbitrary shapes

Abstract

Distributed scattering centre (DSC) is a particular type of scattering centres which has the strongest scattering amplitude among all scattering centres. Furthermore, their distributed signatures in radar images have directly shown geometries of targets. Therefore, DSCs play an important role in target recognition. DSCs are currently described by the attributed scattering centre (ASC) model, which is developed out of the asymptotic expansion solutions to canonical geometries. However, rather than canonical geometries, real radar targets have various geometric structures, which show different signatures in radar images. In order to characterise these various signatures, the parametric model is modified. Scattered fields from planar and single-curved surfaces with arbitrary shapes are studied in this study and motivated by which, the parametric models of DSCs for more general structures are presented. To validate these models, the scattered waves and the post-imaging results simulated by these models are compared with those obtained by a rigorous full-wave numerical method, and those obtained by the conventional ASC model. The comparison results demonstrate these models have a higher accuracy over the conventional model in simulations of scattered waves, as well as inverse synthetic aperture radar image signatures of different geometric structures.