Dual Band Metamaterial Absorber Using Concentric Split-Ring Structure For WLAN/WiMAX Application

A dual band metamaterial absorber using concentric split-ring geometry on a metal-backed dielectric substrate is presented in this article. The design exhibits dual band absorption peaks at frequencies 3.5 GHz and 5.8 GHz respectively, having absorptivity more than 96%, making the design suitable for application over the WLAN and WiMAX bands of operation. The structure utilizes concentric split-ring geometry for the unit cell of the absorber that is responsible for the exquisite metamaterial-like performance of the system. The surface currents on the top and the bottom plane of the structure are examined to analyze the dual band absorption performance. The structure exhibits similar characteristics for both TE and TM modes of polarizations. It is also insensitive to oblique incidence upto ±45°. The simple design and thin substrate used, establish the applicability and the utility of such a structure for practical applications.