A new multiple-input/multiple-output (MIMO) antenna design is introduced for future smartphones. The proposed design contains four pairs of double-fed circular-ring resonators located at different edges of the smartphone printed circuit board (PCB) with an FR-4 substrate and a dimension of 75 × 150 mm ² . The antenna elements are fed by 50-Ohm microstrip-lines and provide polarisation and radiation pattern diversity function due to the orthogonal placement of their feed lines. By inserting a rectangular slot under each microstrip feed-line, the mutual coupling characteristic of the antenna ports is reduced. A good frequency bandwidth ( S ₁₁ ≤ − 10 dB) of 3.3–3.9 GHz has been obtained for the smartphone antenna array. Nevertheless, for S ₁₁ ≤ − 6 dB, this value is 3.1–4.3 GHz. More than 3 dB realised gain and 80% total efficiency are achieved for the single-element radiator. The design provides not only sufficient radiation coverage supporting different sides of the mainboard but also the polarisation diversity. In addition, sufficient properties are obtained in the vicinity of human-hand/human-head. The proposed MIMO antenna design is also capable to generate dual- or multi-band function. Moreover, a new and compact phased array millimeter-wave (mm-wave) antenna design with end-fire radiation beams is introduced which can be easily integrated into smartphones.

中文翻译：

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具有模式多样性的正交双极化MIMO天线阵列，可用于5G智能手机

针对未来的智能手机推出了一种新的多输入/多输出（MIMO）天线设计。提议的设计包含四对双馈圆环谐振器，它们位于具有FR-4基板且尺寸为75×150 mm ²的智能手机印刷电路板（PCB）的不同边缘 。天线元件由50欧姆的微带线馈电，并由于其馈线的正交放置而提供极化和辐射图分集功能。通过在每个微带馈线的下方插入一个矩形缝隙，可以降低天线端口的相互耦合特性。良好的频率带宽（ 小号 ₁₁ ≤ - 3.3-3.9 GHz的10分贝）已经获得用于智能手机天线阵列。然而，对于小号 ₁₁ ≤ - 6分贝，该值是3.1-4.3千兆赫。单元件散热器的实现增益超过3 dB，总效率达到80％。该设计不仅提供了足够的辐射覆盖范围来支持主板的不同侧面，而且还提供了极化分集。另外，在人的手/人的头部附近获得足够的特性。所提出的MIMO天线设计还能够产生双频带或多频带功能。此外，还引入了具有端射辐射束的新型紧凑型相控阵毫米波（mm-wave）天线设计，可以轻松集成到智能手机中。