Forward propagation modeling above gaussian rough surfaces by the parabolic wave equation: Introduction of the shadowing effect

In this paper, a fast method is presented to model the forward propagation above Gaussian rough surfaces and taking into account atmospheric refraction. The method is based on the Discrete Mixed Fourier Transform ( DMFT) solved by the Parabolic Wave Equation, in which the Ament boundary condition with shadowing effect is used at grazing angle. In this model, for a bistatic configuration, the surface height PDF of the illuminated points is derived and it is introduced in the boundary condition. Examples demonstrate the capacities of the method to compute propagation factor above rough surfaces following Gaussian statistics and Gaussian height correlation and the proposed method is validated by comparison to a Monte Carlo approach.