SIMULATIONS OF ROUGH INTERFACE SCATTERING

This paper describes numerical simulations of rough interface scattering. Both Dirichlet and fluid-solid boundary conditions are treated. The Rayleigh-Fourier method is used to compute exact plane-wave scattering amplitudes and results are compared to various approximations. The small-slope approximation of Voronovich performs remarkably well, while the tangent-plane approximation is shown to miss some essential physics of scattering. It is observed that at the Rayleigh angle there is a peak in the backscattering amplitude, even for plane-wave incidence. It is argued that the statistics of plane-wave scattering amplitudes are Gaussian.