Luadang Bancha, Janpangngern Pisit, Pookkapund Khanet, Dentri Sitthichai, Krairiksh Monai, Phongcharoenpanich Chuwong
Faculty of Engineering, Rajamangala University of Technology Rattanakosin, Nakhon Pathom, 73170, Thailand.
School of Engineering, King Mongkut's Institute of Technology Ladkrabang, Bangkok, 10520, Thailand.
Sci Rep. 2024 Apr 27;14(1):9693. doi: 10.1038/s41598-024-60346-6.
This research proposes a broadband unidirectional twin-element multiple-input-multiple-output (MIMO) antenna scheme for mid-band 5G and WLAN applications. The twin-element antenna scheme comprises two single-element antennas, and each single-element antenna consists of a T-shaped hemispherical feeding patch, left- and right-arm radiating patches, and a conjoined triangular ground plane. The twin-element MIMO antenna scheme is integrated with a laptop model functioning as the reflector. The measured impedance bandwidth (|S|, |S|≤ - 6 dB) are 55.32%, covering 3.4-6.0 GHz, and the measured mutual coupling (|S|) is less than - 15 dB. The measured gain at the center frequency (4.5 GHz) is 4.585 dBi. Besides, the measured xz- and yz-plane cross-polarization levels are below - 25 dB and - 15 dB, respectively. The half-power beamwidth (HPBW) in the xz-plane at 3.5, 4.5, and 5.5 GHz are 99°, 92.8°, and 84.2°, and the corresponding HPBW in the yz-plane are 102°, 78°, and 102°. The measured xz- and yz-plane back lobe levels are below - 15 dB across the entire operating frequency band (3.5-5.5 GHz). The radiation pattern of the twin-element MIMO antenna scheme is of unidirectionality. Furthermore, the envelope correlation coefficient and diversity gain of the twin-element antenna scheme are < 0.001 and > 9.99 dB, respectively. The proposed broadband unidirectional twin-element MIMO antenna scheme is thus operationally suitable for mid-band 5G/WLAN communication systems. Essentially, this research is the first to propose a broadband twin-element MIMO antenna scheme for mid-band 5G/WLAN applications.
本研究针对中频段5G和WLAN应用提出了一种宽带单向双元多输入多输出（MIMO）天线方案。双元天线方案由两个单元天线组成，每个单元天线由一个T形半球形馈电贴片、左右臂辐射贴片和一个相连的三角形接地平面组成。双元MIMO天线方案与用作反射器的笔记本电脑模型集成在一起。测量得到的阻抗带宽（|S₁₁|，|S₂₂|≤ -6 dB）为55.32%，覆盖3.4 - 6.0 GHz，测量得到的互耦（|S₁₂|）小于 -15 dB。在中心频率（4.5 GHz）处测量得到的增益为4.585 dBi。此外，测量得到的xz平面和yz平面交叉极化水平分别低于 -25 dB和 -15 dB。在3.5、4.5和5.5 GHz时，xz平面的半功率波束宽度（HPBW）分别为99°、92.8°和84.2°，yz平面相应的HPBW分别为102°、78°和102°。在整个工作频段（3.5 - 5.5 GHz）内，测量得到的xz平面和yz平面后瓣水平低于 -15 dB。双元MIMO天线方案的辐射方向图具有单向性。此外，双元天线方案的包络相关系数和分集增益分别小于0.001和大于9.99 dB。因此，所提出的宽带单向双元MIMO天线方案在操作上适用于中频段5G/WLAN通信系统。本质上，本研究首次提出了一种用于中频段5G/WLAN应用的宽带双元MIMO天线方案。
