A compact U-shaped ultra-wideband (UWB) multiple-input-multiple-output (MIMO) antenna with novel complementary modified Minkowski fractal (CMMF) for isolation enhancement is proposed. This antenna consists of two identical U-shaped monopole elements, a novel CMMF and a slot in the bottom of the ground plane for the isolation enhancement. The novel CMMF is designed by a technique iterated function system (IFS). The overall dimension of this compact antenna is 22 x 28 mm2. The impedance bandwidth of this antenna is 10.35 GHz, ranging from 3.06 GHz to 13.41 GHz. The minimum isolation is 17.07 dB for the operating frequency range and 18.4 dB for the UWB frequency range 3.1 to 10.6 GHz. The diversity parameters are also determined for the proposed MIMO antenna, and all are found satisfactory. The proposed MIMO antenna is fabricated, and its prototype measured results are found in good agreement with the simulated ones.
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