An approximation for bistatic scattering matrix of a target above a ground plane

The paper derives a high-frequency approximation for the scattering matrix of a target placed above an infinite ground plane which can be either perfectly electrically conducting (p.e.c.) or non-metallic. The approximation accounts for electromagnetic interactions between the target and the ground plane, which involves a single reflection from the target and up to two reflections from the ground. It provides the correction for amplitude, phase, and polarization of the scattered signal for both mono- and bistatic configurations. The approximation is validated by application to a test configuration (a p.e.c. sphere over a dielectric half space), for which independent results obtained with the Method of Moments are available.