Electromagnetic Scattering by an Infinite Array of Periodic Broken Wires Buried in a Dielectric Sheet

A general formulation of the scattering of a plane wave from a periodic broken-wire grid buried in a dielectric sheet is described for a general incidence angle and for arbitrary linear polarisation. The approach is applicable for grids in an infinite dielectric and when located at the boundary interface of two dielectrics. The two-dimensional periodicity of the grid enables the scattered field to be expanded in a set of Floquet modes, whose coefficients are obtained from the appropriate current expansion determined by the method of moments. Predicted results are compared with measured transmission characteristics of a grid buried in a thin dielectric sheet.