Scattering of a scalar beam from a two-dimensional randomly rough hard wall: Dirichlet and Neumann boundary conditions

Abstract

We calculate numerically the scattering of a scalar beam that is incident normally upon a large rms height, large rms slope, two-dimensional, randomly rough hard wall. Both Dirichlet and Neumann boundary conditions are assumed in these calculations. The computational approach used is based on writing the integral equation for the value of the normal derivative of the field, and of the field, respectively, on the surface, in the form of an inhomogeneous Fredholm equation of the second kind, and solving it by iteration. Our results display a well-defined peak in the retroreflection direction in the angular dependence of the intensity of the waves scattered incoherently, for both boundary conditions.