Rough Surface Scattering Based on the Specular Point Theory

The average number of specular points per unit area for a two-dimensionally rough surface is derived in terms of the surface statistics. Expressions for the average of the product of the principal radii of curvature of the specular point are also obtained. These quantities are then substituted into the average scattering cross section per unit area derived from the stationary-phase approach, and two probability models are considered. The results are general and apply to bistatic as well as backscatter, and are valid for finitely as well as perfectly conducting surface materials.