Effect of correlation between shadowing and shadowed points in rough surface scattering

Abstract

Shadowing of random surfaces is accounted for by multiplying the Kirchhoff electric current density by a shadowing function. The shadow-corrected incoherent intensity is computed in the backscatter direction and is found to be proportional to the probability of a specular point being illuminated from the source. This probability is computed numerically using an infinite series of integrals, developed by Ricciardi and Sato, and by Monte Carlo computer simulations. The results obtained are compared to the analytic approximations of Wagner and Smith, which neglect correlation between the shadowing points and the shadowed point. Assumptions made by Wagner are explained using the infinite series of integrals. Furthermore, comparison is made to Wagner's results which include correlation between the shadowed point and the shadowing point.