FLEXIBLE BROADBAND METAMATERIAL ABSORBER BASED ON MULTILAYER STRUCTURE IN GHz FREQUENCY RANGE

Abstract

In this work, we propose a flexible, broadband metamaterial absorber using a multilayer structure. Each layer of the proposed metamaterial absorber is designed to consist of simple resonant structures made from graphene conductive ink placed on a flexible polyimide dielectric layer. These two structural layers are stacked to form a multilayer structure. Simulation results show that in the flat state, the material absorbs over 90% of the incident electromagnetic waves in the frequency range from about 4.6 to 12.7 GHz, equivalent to a fractional bandwidth of 93.6%. In the case of bending state, the absorption spectrum is extended to a fractional bandwidth of 116.5%, from 4.26 to 16.14 GHz with a bending radius of 100 mm. The broadband absorption mechanism of the material is clarified by the impedance matching theory and electromagnetic energy distribution.