Radar cross section of a rectangular cavity in a finite ground plane

The monostatic RCS of a large rectangular cavity mounted in a finite ground plane was modeled. Aperture integration (AI) of the waveguide modes was used for the cavity, and ground plane edge effects were accounted for via the uniform geometrical theory of diffraction (UTD). The relative importance of various diffraction mechanisms was investigated, in particular, RCS due to (a) the cavity, (b) the ground plane, and (c) interactions of the cavity with the ground plane. Results from the AI/UTD model were compared with the physical theory of diffraction (PTD) based RAPPORT code; agreement was found to be very good.