In this article, a novel miniaturized concept named strong-coupled frequency selective surface (SC-FSS) with excellent angular stability is presented. First, a conceptual design of SC-FSS is introduced, where the resonant frequencies are insensitive to almost all incident angles. A corresponding equivalent circuit model is developed to interpret the operating principle and formulate relevant design equations with an error of 0.2%. Furthermore, an ultraminiaturized and ultrathin band-stop structure with a unit cell size of λ ₀ /35 and thickness of 0.26 mm ( λ₀ /578) is designed and fabricated to verify this concept. Analysis and experiment show that the proposed band-stop SC-FSS structure can work stably at 2 GHz for both TE and TM modes, even when the incident angle varies from 0° to 84°. The measurement results are consistent with those obtained by full-wave simulations and the equivalent circuit model, which fully demonstrates that the concept of SC-FSS can be widely used in designing antenna reflectors, electromagnetic interference shielding, and angle-insensitive absorbers.

中文翻译：

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具有优异角稳定性的新型小型化强耦合FSS结构

在本文中，提出了一种新颖的小型化概念，即具有出色的角度稳定性的强耦合频率选择表面（SC-FSS）。首先，介绍了SC-FSS的概念设计，其中谐振频率几乎对所有入射角都不敏感。开发了相应的等效电路模型来解释工作原理并制定相关的设计方程，误差为0.2％。此外，具有单位面积尺寸为的超小型化和超薄带阻结构λ ₀ /35和0.26毫米的厚度（ λ ₀ / 578）旨在验证这一概念。分析和实验表明，即使入射角在0°到84°之间变化，所提出的带阻SC-FSS结构也可以在2 GHz的TE和TM模式下稳定工作。测量结果与通过全波仿真和等效电路模型获得的结果一致，这充分证明了SC-FSS的概念可广泛用于设计天线反射器，电磁干扰屏蔽和对角不敏感的吸收器。