A new wideband multiple-input/multiple-output (MIMO) antenna system able to operate in a frequency band ranging between 3.3 and 7.1 GHz is proposed for fifth-generation (5G) new radio applications for future smartphones. The design structure contains four pairs of compact microstrip-fed slot antennas, located at the corners of an FR-4 printed circuit board. Each pair of antennas consists of a radiator with two concentric annular slots, fed by two L-shaped microstrip-feeding lines and provides polarization and radiation pattern diversity function due to the orthogonal placement of their feed-line. In order to reduce the mutual coupling characteristic, we have inserted a rectangular slot under each microstrip feed-line. Besides, we have coupled and linked the two rings by a small gap to combine and move the resonant modes so as to achieve wideband coverage. The measured and simulated results show that the proposed design achieves the desired performance, such as isolation >12 dB, a total efficiency >48%, and an envelope correlation coefficient <0.07. In addition, the radiation pattern, the total efficiency, the realized gain, and the channel capacity are also studied. According to the reached results, the proposed MIMO antenna may be a suitable application-oriented design for 5G mobile communication.

中文翻译：

---

面向 5G 智能手机应用的宽带 MIMO 天线阵列设计与分析

为未来智能手机的第五代 (5G) 新无线电应用提出了一种新的宽带多输入/多输出 (MIMO) 天线系统，该系统能够在 3.3 至 7.1 GHz 的频带范围内工作。该设计结构包含四对紧凑型微带馈电缝隙天线，位于 FR-4 印刷电路板的角落。每对天线由一个带有两个同心环形槽的辐射器组成，由两条 L 形微带馈线馈电，并由于馈线的正交放置而提供极化和辐射方向图分集功能。为了降低互耦合特性，我们在每条微带馈线下方插入了一个矩形槽。除了，我们通过一个小间隙将两个环耦合和链接，以组合和移动谐振模式，从而实现宽带覆盖。实测和仿真结果表明，所提出的设计实现了预期的性能，例如隔离度 >12 dB，总效率 >48%，包络相关系数 <0.07。此外，还研究了辐射方向图、总效率、实现增益和信道容量。根据所达到的结果，所提出的 MIMO 天线可能是适合 5G 移动通信的面向应用的设计。还研究了总效率、实现增益和信道容量。根据所达到的结果，所提出的 MIMO 天线可能是适合 5G 移动通信的面向应用的设计。还研究了总效率、实现增益和信道容量。根据所达到的结果，所提出的 MIMO 天线可能是适合 5G 移动通信的面向应用的设计。