This study presents a circularly-polarised substrate-integrated waveguide end-fire antenna and four-antenna arrays for 5G beam-steering mobile devices at 28 GHz. Polarisation is achieved through implementation of a substrate-integrated waveguide notched-septum polariser. It is then loaded with a dielectric lens to improve gain, axial ratio bandwidth, and circular polarisation (CP) purity. To suppress the mutual coupling between array elements, vias are extended on either side of the lens. It also improves the single-element axial ratio and front-to-back ratio. The antenna's performance is found to be resilient to typical manufacturing tolerances for the lens and via extensions. The element and arrays are manufactured and measured. The prototypes demonstrated an impedance bandwidth of 11.4% with a maximum array gain of 10.5 dBi and a steering range of up to (with reduced performance when steered to ). Within this range, the antenna array demonstrates a gain variation of up to 3 dB and very good CP purity within the radiation half-power beamwidths (HPBWs). A wide single-element elevation HPBW of is also demonstrated. Given its performance and ease of manufacture in a printed circuit board process, the proposed antenna could be a strong candidate for 5G millimetre-wave beam-steering systems.

中文翻译：

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用于5G毫米波波束转向系统的圆极化端射天线和阵列

这项研究提出了一种用于28 GHz 5G波束控制移动设备的圆极化基片集成波导端射天线和四天线阵列。通过实现基板集成的波导缺口隔膜偏振器可实现极化。然后将其装上电介质透镜，以改善增益，轴向比率带宽和圆偏振（CP）纯度。为了抑制阵列元件之间的相互耦合，在透镜的任一侧都延伸了过孔。它还提高了单元素轴向比率和前后比率。天线的性能可以抵抗镜头和通孔延伸部分的典型制造公差。元件和阵列被制造和测量。原型展示了11.4％的阻抗带宽，最大阵列增益为10。 （转向时会降低性能 ）。在此范围内，天线阵列在辐射半功率波束宽度（HPBW）内显示出高达3 dB的增益变化和非常好的CP纯度。的单元素高标高HPBW也得到了证明。考虑到它的性能以及在印刷电路板工艺中的易于制造，拟议中的天线可能是5G毫米波波束控制系统的理想选择。