This paper describes a metamaterial-based miniaturized circularly polarized (CP) antenna with high radiation efficiency and wide beam-width or coverage for 5G indoor application. A novel meta-resonator is first proposed, which is investigated by transmission line and equivalent circuit models. By exploring a split-ring resonator-like meta-resonator structure, a high-Q LC resonator tank is formed. Substantial size reduction and a wide beam-width are achieved. Owing to a uniform field on these multiple capacitive gaps incorporated on this meta-resonator surface, enhanced aperture efficiency and gain are obtained. It is partly inspired by the classical metasurface-based antenna. For validation, a miniaturized CP antenna with a size of 0.29 λ₀ × 0.29 λ₀ × 0.04 λ₀ (where, λ₀ is the free-space wavelength at 3.55 GHz) is fabricated and measured. The fabricated antenna achieves a good bandwidth of 3.30–3.80 GHz that well covers 5G-N78 band, a peak radiation gain of 5.4 dBic, a high radiation efficiency of 90% and a wide half-power beam-width of 91°. It exhibits the merits of compact size, good bandwidth and beam-width, high efficiency, and low-cost, demonstrating good potential in miniaturized 5G indoor systems demanding wide-beam coverage.

中文翻译：

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用于 5G 室内应用的基于超材料的紧凑型宽波束圆极化天线

本文描述了一种基于超材料的小型化圆极化 (CP) 天线，具有高辐射效率和宽波束宽度或覆盖范围，适用于 5G 室内应用。首先提出了一种新型元谐振器，并通过传输线和等效电路模型对其进行了研究。通过探索类似裂环谐振器的元谐振器结构，形成了高Q LC谐振槽。实现了显着的尺寸减小和宽波束宽度。由于在这个元谐振器表面上结合的这些多个电容间隙上的均匀场，获得了增强的孔径效率和增益。它的部分灵感来自经典的基于超表面的天线。为了验证，尺寸为 0.29 λ ₀  × 0.29 λ ₀  × 0.04 λ的小型化 CP 天线₀（其中，λ ₀是 3.55 GHz 的自由空间波长）被制造和测量。制造的天线实现了 3.30-3.80 GHz 的良好带宽，很好地覆盖了 5G-N78 频段，峰值辐射增益为 5.4 dBic，辐射效率高达 90%，半功率波束宽度为 91°。它具有体积小、带宽和波束宽度好、效率高、成本低等优点，在需要宽波束覆盖的小型化5G室内系统中显示出良好的潜力。