Dual Nonagon-Shaped Elements UWB MIMO for 5G and Expected Mid-Band 6G Communications

Abstract

A new compact-size, highly isolated dual-element ultra-wideband (UWB) MIMO antenna for modern wireless communications is designed in this paper. This design is composed of two identical nonagon-shaped (nine-sided polygon) monopoles placed in perpendicular geometry to rise the isolation between the two antenna elements. In addition, a rectangular-shaped partial ground plane was used to boost the bandwidth of the proposed design. This design exhibits UWB with a return loss of less than -10 dB in the frequency range of 2.92 GHz to 20.59 GHz and a fractional bandwidth (FBW) of 150.32 % making it suitable for mid-band 5G and expected 6G communications. The maximum obtained correlation coefficient (ECC) was 0.0071, and the overall isolation was better than -24 dB. The proposed design was built over Rogers RT5880 substrate material with a relative permittivity of 2.2 and an overall size of 34 × 64 × 0.508 mm3. The simulated results of the proposed antenna have been obtained using ANSYS HFSS software.