Thin composite matched impedance magneto-dielectric metamaterial absorbers

Low loss magneto-dielectric substrates when used as substrates for patch antennas are shown to miniaturize the aperture size of the patch antennas while preserving or improving the operational bandwidth. We demonstrated that the properties of a PEC backed low loss matched impedance magneto-dielectric metamaterial slab with frequency dependent permittivity and permeability could effectively be achieved using a multi-layered thin composite structure. In this paper, we demonstrate that modified equations from [2] can be used to optimize thin composite structures to design high loss matched impedance magneto-dielectric metamaterials for absorber applications above 1 GHz. The design technique is based on using a genetic algorithm (GA) to optimize thin multi-layered metallo-dielectric metamaterial slab comprised of a periodic array of electrically small metallic frequency selective surface (FSS) screen sandwiched between two different dielectric materials, one of which is backed by a perfectly conducting ground plane. Examples will be presented to demonstrate the effectiveness of the optimized absorber structures.