Broadband metamaterial absorber with double resonant modes using single-layer substrate

A novel broadband metamaterial absorber (MA) is proposed in this paper. The element of absorber consists of square substrate, top and bottom metal layer. A circular patch is printed on the top layer and located in the center of element. Other three circular patches are located in three corners and connected with the center patch, respectively. The mechanism is analysed and discussed with the equivalent circuit and parameter study. It exhibits double resonant frequencies corresponding to different working modes and achieves broadband of good absorption. The structure has a thickness of 1.0 mm and two resonate frequencies of 7.94 GHz and 8.65 GHz. The experiment results are good agreement with the simulated ones. The simple structure shows a relative bandwidth of 19%, polarization insensitive and wide operating angle. The proposed absorber can be widely applied in national defence and civil fields due to its simple structure and good absorption characteristic. (C) 2020 Elsevier GmbH. All rights reserved.