A compact modified sierpinski carpet fractal UWB MIMO antenna with square-shaped funnel-like ground stub

In this paper, a compact modified Sierpinski carpet fractal ultra-wideband (UWB) multiple-input-multiple-output (MIMO) antenna with a square-shaped funnel-like ground stub is presented and experimentally investigated. Miniaturization and wideband performance are achieved by using the proposed fractal structure. Iterated function system (IFS) method is used to design the proposed fractal structure. The self-similarity dimension of the proposed fractal structure is 1.72. The dimension of the proposed MIMO antenna is 24 x 30 mm(2) and consists of two novels modified Sierpinski carpet fractal monopole-antenna elements. The impedance bandwidth of the presented antenna is 9.6 GHz (S-11 < -10 dB) ranging from 3 GHz to 12.6 GHz with isolation better than 16.3 dB, which is achieved by using square-shaped funnel-like ground stub with a vertical slot. The various parameters of diversity performance are also calculated. The simulated and measured results of the presented antenna are comparable, which indicates that the presented antenna can be utilized in UWB applications. (C) 2020 Elsevier GmbH. All rights reserved.