This letter describes the design of a broadband and FSS-based transmitarray (TA) antenna for 5G millimeter-wave applications. Two different elements are proposed to avoid the issues of the geometrical parameter resizing of the elements to obtain a 2 bit transmission phase of {−π, −π/2, 0, π/2} to achieve a TA antenna with wideband behaviors. Both of the two proposed elements show low insertion loss of below 1 dB from 24 to 38 GHz. Moreover, the two elements can achieve two sets of discrete transmission phases of {– π, 0} and {−π/2, π/2} without resizing their dimensions, respectively. A TA prototype based on the proposed two elements is designed and fabricated. The measured results agree very well with the simulated ones. The measured 1 and 3 dB gain bandwidth is 28.0–37.5 GHz (29.0%) and 25.1–39.1 GHz (43.7%), respectively. A peak aperture efficiency of 44.7% at 30 GHz is experimentally obtained with a realized gain of 26.1 dBi.

中文翻译：

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用于 5G 毫米波应用的宽带和基于 FSS 的发射阵列天线

这封信描述了用于 5G 毫米波应用的宽带和基于 FSS 的发射阵列 (TA) 天线的设计。提出了两种不同的元件来避免元件的几何参数调整大小以获得 {-π, -π/2, 0, π/2} 的 2 位传输相位的问题，从而实现具有宽带行为的 TA 天线。两个提议的元件都显示出从 24 到 38 GHz 低于 1 dB 的低插入损耗。此外，这两个元件可以在不调整其尺寸的情况下分别实现{-π, 0}和{-π/2, π/2}的两组离散传输相位。设计并制造了基于所提出的两个元素的 TA 原型。测量结果与模拟结果非常吻合。测得的 1 dB 和 3 dB 增益带宽分别为 28.0–37.5 GHz (29.0%) 和 25.1–39.1 GHz (43.7%)。