This article presents a new method of enhancing the capacitance of a single-layer conformal frequency selective surface (FSS) for multifunctional operation. The unit cell of the FSS consists of gridded square loop-loaded modified Jerusalem cross (JC) element. End capacitance of the conventional JC FSS is enhanced by placing parallel diagonal strips, resulting in a pair of reflection zeros near the sidebands. The modified geometry provides high selective stopband filtering that reflects the signal at 20.16 GHz with S ₂₁ < −10 dB stopband bandwidth of 20.52%. The FSS shows stable stopband reflection up to a high incidence angle of 85°. The stability in the filter response is also achieved at various conformal angles. The proposed FSS is optimized for dual-band near-perfect absorption. At two resonances 12.76 and 22.54 GHz, the absorption are 99.88% and 99.1%, respectively. Prototypes of the stopband FSS and the dual-band absorber are fabricated to verify the feasibility of the proposed concept. The measured filter and absorber responses are found consistent with the simulated results. As a conformal multifunctional structure, the proposed FSS has the merits of electromagnetic interference shielding and radar cross section reduction in stealth application.

中文翻译：

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用于高角度稳定阻带滤波和微波吸收的具有增强电容负载的保形多功能 FSS

本文提出了一种增强单层共形频率选择表面 (FSS) 的电容以实现多功能操作的新方法。FSS 的单位单元由网格方形环加载的修改耶路撒冷十字 (JC) 元素组成。传统 JC FSS 的端部电容通过放置平行对角带来增强，从而在边带附近产生一对反射零点。修改后的几何结构提供了高选择性阻带滤波，可反射 20.16 GHz 的信号S ₂₁ < -10 dB 阻带带宽为 20.52%。FSS 在高达 85° 的高入射角时表现出稳定的阻带反射。滤波器响应的稳定性也在各种共形角处实现。所提出的 FSS 针对双波段近乎完美的吸收进行了优化。在两个共振 12.76 和 22.54 GHz 处，吸收分别为 99.88% 和 99.1%。制作了阻带 FSS 和双频带吸收器的原型，以验证所提出概念的可行性。测得的滤波器和吸收器响应与模拟结果一致。作为一种保形多功能结构，所提出的FSS在隐身应用中具有电磁干扰屏蔽和雷达截面减小的优点。