Jeong Heijun, Lim Sungjoon
School of Electrical and Electronic Engineering, Chung-Ang University, Heukseok-Dong, Dongjak-Gu 156-756, Republic of Korea.
Sci Rep. 2018 Jun 15;8(1):9226. doi: 10.1038/s41598-018-27609-5.
In this study, we propose a broadband frequency-reconfigurable metamaterial absorber using a novel switchable ground plane (SGP). A double resistive square-ring resonator is introduced for broadband absorption. The distance between the top resonator pattern and the ground plane determines the resonant frequency; the proposed SGP is thus capable of switching the absorption frequency band. The SGP can be either ground or reactive, by switching the PIN diodes on and off, respectively. The SGP is placed as the middle layer, between the top pattern and the bottom ground plane. In the low frequency band, the SGP becomes reactive and the bottom ground plane works as the ground plane of the absorber. In the high frequency band, the SGP works as the ground plane and the bottom ground plane does not affect the absorber. The proposed idea is demonstrated via full-wave simulations and measurements. The absorption of the fabricated sample with 27 × 27 unit cells is measured under normal incidence. When the PIN diodes of the SGP are turned on, an absorption higher than 90% is achieved between 3.5-11 GHz. When the PIN diodes of the SGP are turned off, an absorption higher than 90% is achieved between 1.7-5.2 GHz.
在本研究中，我们提出了一种使用新型可切换接地平面（SGP）的宽带频率可重构超材料吸收体。引入了双电阻方环谐振器以实现宽带吸收。顶部谐振器图案与接地平面之间的距离决定了谐振频率；因此，所提出的SGP能够切换吸收频段。通过分别打开和关闭PIN二极管，SGP可以是接地的或呈容性的。SGP放置在顶部图案和底部接地平面之间的中间层。在低频段，SGP呈容性，底部接地平面作为吸收体的接地平面。在高频段，SGP作为接地平面而底部接地平面不影响吸收体。通过全波模拟和测量验证了所提出的想法。在正入射下测量了具有27×27个单元的制造样品的吸收率。当SGP的PIN二极管打开时，在3.5 - 11 GHz之间实现了高于90%的吸收率。当SGP的PIN二极管关闭时，在1.7 - 5.2 GHz之间实现了高于90%的吸收率。
