A compact five-port multi-input multi-output (MIMO) antenna for n79 (4.4–5 GHz) 5G band exhibiting pattern and polarization diversity with good isolation is proposed in this paper. This MIMO antenna system comprises of four linearly polarized (LP) endfire monopole antenna elements and one broadside L-shaped slot circularly polarized (CP) antenna element, which provides both pattern and polarization diversity. A T-shaped slot as a decoupling structure is further used to improve the interport isolation by 4 dB. The return loss bandwidth for all antenna elements is in the desired frequency range, and antenna elements provide isolation better than 23 dB. The pattern and polarization diversity provide a low envelope correlation coefficient and good isolation between any two-port of the MIMO antenna. For experimental verification, the proposed 5-port MIMO antenna system is fabricated and measured, which provides decent agreement with the simulated performance.

本文提出了一种紧凑型五端口多输入多输出 (MIMO) 天线，适用于 n79 (4.4–5 GHz) 5G 频段，具有良好的隔离度和方向图和极化分集。该 MIMO 天线系统由四个线极化 (LP) 端射单极天线元件和一个宽边 L 形槽圆极化 (CP) 天线元件组成，可提供方向图和极化分集。进一步使用 T 形槽作为去耦结构，将端口间隔离度提高 4 dB。所有天线元件的回波损耗带宽都在所需的频率范围内，并且天线元件提供优于 23 dB 的隔离。方向图和极化分集在 MIMO 天线的任何两个端口之间提供了低包络相关系数和良好的隔离。为了实验验证，