부산대학교 도서관

This paper introduces a novel 4-element MIMO antenna engineered for prospective 5G applications. The designed MIMO antenna comprises four identical circular patches, each strategically perforated to attain the desired outcomes. The antenna’s substrate is constructed using RogersRT/duroid 5880, featuring a dielectric constant of 2.2 and a height of 1.2 mm. The size of the suggested array antenna is $25 \times 25 \times 1.2 \mathrm{~mm}^{3}$. Employing the high-frequency structure simulator (HFSS), the suggested antenna undergoes simulation and study. Functioning as a wideband antenna, it resonates across the frequency spectrum of 25.10 to 30.52 GHz, exhibiting a substantial bandwidth of 5.42 GHz, a reflection coefficient of approximately -25 dB at 28.5 GHz and an impressive isolation under $\mathbf{- 2 5} \mathrm{dB}$. The antenna demonstrates high gains of about 7.26 dBi at 28.5 GHz, a radiation efficiency around $99 \%$ at 28 GHz, an envelope correlation coefficient $(E C C)\lt0.01$ and a diversity gain $\gt9.95 \mathrm{~dB}$, well-suited for the demands of next generation 5G use case. Specifically, the suggested array antenna spans the $\mathbf{n 2 5 7}$ band ($\mathbf{2 6 . 5 0 - 2 9 . 5 0}$ $\mathbf{G H z}$) and the $\mathbf{n} 261$ band ($\mathbf{2 7 . 5 0 - 2 8 . 3 5} \mathbf{G H z}$), which are widely utilized. Comprehensive results, encompassing return loss, gain, and various parameters, coupled with the antenna’s compact size, affirm the potential utility of the proposed MIMO antenna for 5 G use cases.