Scattering from metallic gratings made of various strip conductivity profiles

Metallic gratings have long been used as frequency selective surfaces for applications ranging from beam splitters to polarization filters. These gratings are generally modeled as an infinite array of evenly spaced metallic strips. These structures are usually modeled by assuming that each of the strips in the grating has an infinite conductivity or that all strips are made of the same finite conductivity. An analytical method, based on the electric field integral equation and the method of moments, is developed in which the conductivity of each strip is taken into account. Various strip conductivity profiles are analyzed for their effect on the radar cross section area (RCS). The induced currents on each strip are solved to calculate the scattered field.