The broadband absorber based on plasma metastructure with spiral resonators

Abstract

In this paper, firstly, a dual narrowband absorber based on plasma metastructure with a single spiral resonator is proposed, whose absorption rate in the frequency bands of 19.60∼20.21 GHz and 23.08∼25.55 GHz is higher than 90%. Through continuous optimization, a broadband absorber composed of four spiral structures with different sizes is finally obtained. When the absorption is larger than 90%, the absorption frequency domain of this absorber can cover from 21.11 to 28.08 GHz, with a relative bandwidth of 28.3%. What's more, the absorption principle of spiral absorber has also been studied in the process of parameter discussion in depth. The design process of this absorber also contributes to a new approach for expanding the operation bandwidths of other similar ones. Compared with the conventional absorbers, the proposed device is more compact, and superior in absorption, with the designable electromagnetic parameters of the material. In addition, the given absorber has exceedingly extensive application prospects in the fields of detection, imaging, and electromagnetic stealth.