A common grounded ultra-wideband diversity/MIMO antenna with high inter-element isolation

An ultra-wideband (UWB) multiple input multiple output (MIMO) antenna with two ports, a low profile of 0.354λ₀ × 0.734λ₀, with good isolation is suggested. The antenna is designed to be compact and single-sided by using modified Koch fractal-based radiators in conjunction with coplanar waveguide (CPW) feeding. A slotted octagonal ground plane and an octagonal modified Koch fractal radiator with CPW feeding make up the basic antenna, which achieves a UWB response. MIMO capacity is achieved by placing two identical parts in opposite directions in a 180° rotational arrangement, which successfully realizes the diversity performance. The ground connection and strong isolation between the elements are established by a meander line construction positioned in the center. The antenna maintains an efficiency of over 86% and shows a peak gain of 6.1 dB. Additionally, it maintains acceptable MIMO diversity parameters like envelope correlation coefficient of less than 0.05, diversity gain of almost 10 dB, channel capacity loss of less than 0.4 bps/Hz, total active reflection coefficient of less than 10 dB, and mean effective gain ratio of 0 dB over the operating band, while achieving an impressive 10 dB impedance bandwidth (IBW) spanning (126.48%) from 3.24 to 14.39 GHz. Its exceptional performance is shown by the respectable outcomes of S-parameters and MIMO diversity evaluations, as well as a thorough time-domain study. Due to its high data rates, scalability, spectrum efficiency, and ease of integration, the UWB MIMO antenna could be suitable for internet of things-based security system for smart offices.