Design of a Conductive FSS based Ultrathin Absorber Using Impedance Analysis Method of Equivalent Circuit Model

In this paper, a conductive frequency selective surface (FSS) based ultrathin absorber is designed using impedance analysis of its equivalent circuit model. The proposed impedance analysis also helps to understand the absorption mechanism of conductive FSS based ultrathin absorbers. The unit cell of the designed absorber consists of a conductive square ring FSS on a low-loss grounded λ₀/32 thick substrate. The proposed absorber is fabricated and measurement results are provided to validate the circuit simulated result of the equivalent model and full-wave simulation result.