Refractive properties of wire-grid metamaterials

This paper reports on a quantitative analysis of the electromagnetic properties of an arrangement of periodic metallic grids devised to provide in the 12.5-20.0GHz frequency range a refractive index less than unity with view to enhance the functionalities of microwave horn antennas. Based on an analytical model, the ultra-refractive behavior of the metamaterial structure is demonstrated by the impedance and refractive index values retrieved from simulated scattering parameters.