Use of supercomputers to evaluate singly and multiply scattered electromagnetic fields from rough surfaces

Full wave expressions for the singly and the doubly scattered electromagnetic fields from one-dimensional rough surfaces are computed. The singly scattered like- and cross-polarized fields are expressed in terms of one-dimensional integrals. However, the doubly scattered full wave solutions are expressed in terms of two- and three-dimensional integrals. To compute the like- and the cross-polarized multiple scattered fields a supercomputer must be used. The results indicate that double scatter in the backward direction is significant for near normal incidence when the mean square slopes of the highly conducting rough surfaces are larger than unity.