FVTD simulation for random rough dielectric surface scattering at low grazing angle

The Finite volume time domain (FVTD) method is applied to electromagnetic w ave scattering from random rough dielectric surfaces. In order to gain a be tter understanding of physics of backscattering of microwave from rough sur face, this paper treats both horizontal and vertical polarizations especial ly at low- grazing angle. The results are compared with those obtained by t he Integral equation method and the small perturbation method as well us wi th the experimental data. We have shown that the present method yields: a r easonable solution even at LGA. It should be noted that the number of sampl ing points pet wavelength for a rough surface problem should be increased w hen more accurate numerical results are required, which fact makes the comp uter simulation impossible at LGA fur a stable result. However, when the ex trapolation is used for calculating the scattered field, an accurate result can be estimated. If we want to obtain the ratio of backscattering between the: horizontal and vertical polarization, we do not need the large number of sampling points.