Imaging of Bunkers Under Slightly Rough Terrain With Clutter-Suppressed, Subsurface Interferometric SAR

A subsurface interferometric synthetic aperture radar (SAR) imaging technique is proposed for the detection and localization of clandestine underground facilities in the presence of a rough ground surface. The new approach consists of a two-step procedure: first, exploiting the distinctive scattering behaviors of the ground surface and the target, clutter suppression is performed with a polarimetric difference operation that does not alter the propagation phase of the target scattered signal, and then, a subsurface interferometric algorithm is applied to infer target depth by correlating the clutter-suppressed images obtained at two observation angles. The performance of the overall sensing algorithm for scene depth profile mapping from an airborne system is demonstrated with full-wave simulation data.