Artificial impedance surfaces based on ferromagnetic wires

Abstract

Ferromagnetic wires are proposed to engineer artificial impedance surfaces. The solution to the scattering problem of a grid of wires in the proximity of a ground plane is solved, and explicit expressions for the equivalent surface impedance and reflection coefficient are formulated. Due to the wide variety of electromagnetic effects excited by the wires (magnetoimpedance effect, magnetic dipolar excitation, inter-coupling between both effects and higher order effects) ferromagnetic wires provide more design flexibility than state of the art impedance surfaces. As a practical example, we present the design of a thin electromagnetic absorber for the case of dominant magnetic dipolar excitation.