Minimally Coupled Two-Element MIMO Antenna with Dual Band (28/38 GHz) for 5G Wireless Communications

This paper presents a dual-band 28/38 GHz two elements multiple-input multiple-output (MIMO) antenna with high isolation for 5G applications. The suggested antenna is a monopole with rectangular and triangle stubs added to the patch and a partial ground plane to achieve the dual band’s behavior. Two elements of the suggested antenna are combined and placed orthogonally to achieve the high isolation features of the MIMO configuration at 28/38 GHz. The MIMO configuration has a size of 27.65 ×\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\times$$\end{document} 12 ×\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\times$$\end{document} 0.273 mm3. The suggested MIMO prototype is fabricated and tested. The tested results achieved dual frequency bands with S11 lower than − 10 dB within two frequency bands (26–30 GHz and 36–41.5 GHz) and S21 lower than − 20 dB through the two operated bands. The suggested antenna has semi-omnidirectional radiation patterns in both planes. As well, its measured peak gain is 5.2 dBi and 5.3 dBi at the two operated frequency bands, respectively. Also, the MIMO parameters are extracted to validate the simulated results. The simulated and tested results have a good matching within the two operating bands which suggests the proposed structure be utilized in 5G communications.