SCATTERING BY LARGE STRUCTURES WITH PERIODIC SURFACES: A PROTOTYPE PROBLEM

Abstract

A hybrid method which uses both numerical and asymptotic techniques is described and applied to the scattering of an electromagnetic wave off a large corrugated circular cylinder. The radius of the cylinder is large compared to the wavelength of the incident radiation, but the corrugation height and period are of the same order as the wavelength. This problem is a prototype of a more general situation where the surface of a target is covered with a periodic coating. The method of attack essentially blends boundary layer theory, which describes the local scattering behavior of the surface, and the theory of geometrical optics which gives a global description of the scattering. Although the hybrid method is only developed here for this simple model, its applicability for other targets is clear. [Vol. 11, No. 1 (1996), pp 57-62, Special issue on Applied Mathematics: Meeting the challenges presented by computational electromagnetics]