Design and analysis of a compact UWB MIMO antenna incorporating fractal inspired isolation improvement and band rejection structures

Abstract

This paper numerically proposes and experimentally investigates a compact coplanar waveguide fed two element ultra-wideband (UWB), multiple-input–multiple-output (MIMO) antenna array accompanying peak isolation and triple band notch mechanism. The proposed antenna consists of two identical printed monopole elements along with the incorporation of multiple 2nd order Hilbert defects in the ground structure and proposes to incorporate three different mechanisms to reduce the electromagnetic interference of the UWB antenna with existing narrowband systems. The measured impedance bandwidth for the intended antenna ranges from 2.7 GHz to 11.22 GHz. The incorporation of notch mechanisms provides interference suppression at the C-band (3.7–4.2 GHz), WLAN (5.15–5.825 GHz), and X-band communication (7.9–8.4 GHz). The overall size of the intended UWB MIMO antenna is 30.75 mm × 37.80 mm. Moreover, the diversity parameters of the proposed UWB MIMO antenna are numerically calculated and empirically investigated, these calculations and investigations depicts high diversity performance. It is noteworthy to observe that the spacing between the elements is staggeringly reduced to 2 mm. The concurrence among the diverse numerical and experimental outcomes supports the candidature of the suggested layout for portable UWB as well as UWB MIMO systems.