A two-scale model for the ocean surface bistatic scattering

An improvement of the two-scale model for the solution of the electromagnetic bistatic scattering from sea surface is presented. The simplest two-scale model combines the small perturbation theory with geometrical Optics. A cut-off frequency separating the two domains has to be chosen. This is a difficult task, since, except for low winds, the domains of validity of the two approximations do not overlap. We suggest to replace the small perturbation theory by the Small Slope Approximation of Voronovich. It allows the cut-off spatial frequency to be shifted so that the use of geometrical Optics is restricted to larger scales.