MIMO Antennas for Smart 5G Devices Using UWB Technology

A novel Multiple-Input Multiple-Output (MIMO) antenna is proposed for ultra-wideband (UWB) applications. The designed MIMO structure consists of two simple square monopole antennas integrated with a slotted ground plane. The antenna achieves an impedance bandwidth ranging from 2.8 GHz to 10.8 GHz, with an isolation level better than −30 dB. To mitigate interference with WiMAX applications, a notched band is introduced between 3.3 GHz and 3.8 GHz using U-shaped and L-shaped slots. Additionally, to enhance isolation between the monopole antennas, two distinct parasitic structures are positioned at the bottom of the substrate. The proposed MIMO antenna, with compact dimensions of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$25 \times 38 ~\text{mm}^{2}$</tex>, has been fabricated and tested. Both simulation and experimental results confirm that the proposed design performs efficiently for UWB applications with band-notch functionality, making it a suitable candidate for modern wireless communication systems.