Scattering by dielectric filled grooves using a combination of higher order impedance boundary conditions and edge conditions

In this paper higher order impedance boundary conditions, (HOIBC), are used in combination with edge conditions to solve the problem of scattering by a two dimensional dielectric filled groove in an infinite ground plane. This object can be used to model a perturbation in an otherwise homogeneous large conducting body such as hatches, ports, and seams between panels. The conducting boundary of the groove is of arbitrary shape, and the dielectric filling the groove is assumed to be comprised of discrete layers oriented parallel to the ground plane. Higher order impedance boundary conditions which are determined using a spectral domain method, are applied to the problem of scattering by multilayer grooves with arbitrary profiles, and the effects of discontinuities on the boundary conditions, i.e. sharp corners, are addressed by incorporating the proper edge conditions. Monostatic and bistatic RCS results will be compared to those from an exact solution which is based upon a mode matching/scattering matrix approach for the interior region.