Optimized Frequency Selective Surface for the Design of Magnetic Type Thin Broadband Radio Absorbers

Abstract

A novel frequency selective surface for expansion of operating frequency range of magnetic-type radio absorbers was elaborated. Frequency selective surface represents an array of flat electrically conductive elements deposited on the polyethylene terephthalate (PET) foil. The elements have a closed-loop structure on the one side of the foil, and on the opposite side, the conductive elements have the shape of solid fragments which connect projections of the neighboring closed loops. The advantage of such frequency selective surface design is that owing to capacitive shunting one can achieve the value of frequency selective surface quality factor (Q-factor) as low as 0.5. Operating frequency range and thickness of designed radio absorbers depend on the composition of polymer-magnetic material and the position of frequency selective surface therein.