In this article, a compact frequency selective surface (FSS) is implemented using a modified metallic square loop structure for ultrawide band (UWB) stop behavior. The proposed structure exhibits wideband rejection over the entire UWB, ranging from 3.1 to 10.8 GHz. The proposed structure manifests polarization independent characteristics and provides a stable frequency response for normal and oblique angles under both transverse electric (TE) and transverse magnetic (TM) incident polarization. The angular stability for various polarization angles is also obtained. This structure provides a −10dB wide impedance bandwidth of 110.79%. The maximum relative deviation in between transmission zero frequency and angularly incident frequency is 5.9% and 6.2% at 80˚ TE and TM polarized wave, respectively, with attenuation more than 45 dB. The unit cell of the proposed FSS is imprinted on single-layer FR4 substrate of the dimensions 6 × 6 mm ² , which is 0.062× 0.062 λ, where λ is the wavelength of lower cut-off frequency and is by far the smallest design for the desired UWB rejection FSS.

中文翻译：

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单边改进方环UWB选频面的设计与分析

在本文中，使用用于超宽带 (UWB) 停止行为的改进金属方形环路结构实现了紧凑的频率选择表面 (FSS)。所提出的结构在整个 UWB 范围内表现出宽带抑制，范围从 3.1 到 10.8 GHz。所提出的结构表现出与极化无关的特性，并在横向电 (TE) 和横向磁 (TM) 入射极化下为法向和斜角提供稳定的频率响应。还获得了各种偏振角的角稳定性。这种结构提供了 110.79% 的 −10dB 宽阻抗带宽。传输零频率和角入射频率之间的最大相对偏差在 80˚ TE 和 TM 极化波下分别为 5.9% 和 6.2%，衰减超过 45 dB。 ² , 即 0.062× 0.062 λ, 其中λ 是较低截止频率的波长，是迄今为止所需 UWB 抑制 FSS 的最小设计。