In this paper, a super-compact ultra-wideband (UWB) metamaterial absorber (MMA) is presented. The absorber design consists of an inverted L-shaped structure and a diagonal rectangular-shaped structure. The capacitive coupling between these two structures not only provides UWB nature but also provides a super-compact absorber design. The dimension of the unit cell arrangement is 5 × 5 mm2 and printed on a low-cost FR-4 substrate of thickness 1.54 mm (0.061λlowest). The design absorber provides more than 97% absorptivity from 12 to 21 GHz for normal incidence electromagnetic (EM) wave. However, the proposed MMA has a full width at half maximum absorption bandwidth of 11.71 GHz from 10.34 to 22.05 GHz. Moreover, the surface current distributions have been analyzed to understand the absorption mechanism of the MMA. The stability of the proposed design is validated with different incident angles (for TE and TM modes) and different polarization angles. Finally, the absorber design is fabricated and verified experimentally. Furthermore, the UWB frequency range, high absorption, ease in design and fabrication, and cost-effective make it suitable for different quality applications in stealth technology, thermal imaging, radar detection, antenna systems, and other EM devices.

中文翻译：

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超紧凑超宽带（UWB）偏振和入射角无关超材料吸收体的实验验证

在本文中，提出了一种超紧凑超宽带（UWB）超材料吸收器（MMA）。吸收器设计由倒L形结构和对角矩形结构组成。这两种结构之间的电容耦合不仅提供了超宽带特性，还提供了超紧凑的吸收器设计。单元电池排列的尺寸为 5 × 5 mm2并印刷在厚度为 1.54 毫米（0.061λ最低）。该设计吸收器在 12 至 21 GHz 范围内为正入射电磁 (EM) 波提供超过 97% 的吸收率。然而，所提出的 MMA 在 10.34 至 22.05 GHz 范围内具有 11.71 GHz 的半峰全宽吸收带宽。此外，还分析了表面电流分布以了解 MMA 的吸收机制。所提出设计的稳定性通过不同的入射角（对于 TE 和 TM 模式）和不同的偏振角进行了验证。最后，制作了吸收器设计并进行了实验验证。此外，UWB 频率范围、高吸收、易于设计和制造以及成本效益使其适用于隐形技术、热成像、雷达探测、天线系统和其他 EM 设备中的不同质量应用。