Dual-Band Energy-Selective Surface With Wide Absorption Band

A dual-band energy-selective surface (ESS) that achieves stealth for in-band and out-of-band electromagnetic (EM) waves is proposed in this article. It consists of an absorptive layer and a switchable layer. The absorptive layer integrates cross-shaped and gear-shaped metal patches loaded with resistors and p-i-n diodes. The switchable layer uses double concentric ring slots embedded with diodes. Compared with existing ESSs, the proposed ESS controls the absorption band by integrating diodes in the absorption layer. Furthermore, high-power microwaves (HPMs) inside and outside the passbands are absorbed. The experimental results demonstrate that the ESS exhibits the insertion loss (IL) of 0.8 dB at 3.76 and 5.86 GHz when the low-power signal is incident. The out-of-band absorption bands range from 1.81 to 3.43 GHz and from 4.1 to 5.59 GHz. Under HPM, the shielding effectiveness (SE) is more than 10 dB in the range of 1–6.3 GHz. Also, the relative bandwidth of the absorption band reaches 108% (1.86–6.3 GHz). By integrating HPM shielding, wideband absorption, and dual-band operation, this ESS shows significant application prospects in EM compatibility and stealth technologies.