The Brewster angle effect on sea surface scattering for near-grazing incidence

The radar cross section of sea clutter at (or near) the horizon is a critical parameter in naval radar system performance evaluation. At the low grazing angles and ranges involved, the existing data base is quite limited. At near-grazing illumination, the radar receives an echo from the sea surface which is characterized by short bursts of power. These are significantly stronger than the random average scattering. The problem of developing a model for rough surfaces is a very difficult one, since, at best, the scattering coefficient σ⁰ is dependent upon (at least) radar frequency, geometrical and physical parameters, incident and observation angles, as well as polarization. In this paper the development of a theoretical two-scale model describing bistatic reflectivity is presented as well as the numerical results computed for the bistatic radar cross-section from random rough surfaces especially from the sea surface. The numerical results for the bistatic scattering coefficient for the sea surface are used to show the Brewster angle effect on near-grazing angles