This paper proposes a novel subwavelength single-layer reflectarray antenna unit cell operating in X-band, composed of double hexagonal rings and a hexapole. This new cell is not sensitive to TE and TM polarizations. Infinite array approach has been used to determine the reflection phase curve. The proposed element has more than 575° linear phase range in 8.5–11 GHz frequency band by varying the radius of the outer ring. The scattering parameters of an infinite reflectarray using the proposed element are measured by the waveguide simulator which takes into account the effects of the mutual coupling. A 277-element center-fed reflectarray antenna using this cell is designed, fabricated and measured to verify the broadband property of the proposed element. The measurement results show about 27.5% 3-dB gain bandwidth and 22.8 dB maximum gain at 10 GHz, which is equivalent to about 32% aperture efficiency.

中文翻译：

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双六边形环六极宽带单层反射阵列天线的设计

本文提出了一种新型亚波长单层反射阵列天线单元，工作在 X 波段，由双六边形环和六极组成。这种新电池对 TE 和 TM 极化不敏感。无限阵列方法已被用于确定反射相位曲线。通过改变外环的半径，所提出的元件在 8.5-11 GHz 频带内具有超过 575° 的线性相位范围。使用所提出的元件的无限反射阵列的散射参数由波导模拟器测量，该模拟器考虑了相互耦合的影响。设计、制造和测量了使用该单元的 277 单元中心馈电反射阵列天线，以验证所提议单元的宽带特性。测量结果显示在 10 GHz 时大约 27.5% 的 3-dB 增益带宽和 22.8 dB 的最大增益，