Non-conventional leather substrate based high isolation wideband MIMO antenna for body-centric applications

Abstract

This work presents the design of a dual-port high isolation compact wideband wearable multiple-input multiple-output (MIMO) antenna employing a non-conventional leather substrate material. The designed antenna structure comprises defected structure at the ground plane, including two semicircular slots and two 'H' shaped stubs in the cascaded form to minimize the coupling effect between the antenna ports. The antenna works over the 2.22–8 GHz frequency range with a fractional bandwidth of 113.12 %, covering the application bands of WLAN (2.4–2.484 GHz), WiMAX (3.2–3.85 GHz), WLAN (5.15–5.35 GHz/5.725–5.825 GHz), C band downlink/uplink (3.7–4.2 GHz/5.925–6.425 GHz) and downlink defense (7.2–7.7 GHz) band. The suggested antenna provides port isolation above 27 dB, envelope correlation coefficient (ECC) under 0.09, diversity gain (DG) above 9.94 dB, channel capacity loss below 0.33 Bits/Sec/Hz, low magnitude ratio between mean effective gains of two ports (<0.1 dB), and a stable total active reflection (TARC) over the active spectral region. The designed antenna offers a SAR value less than the threshold level (<1.6 W/kg). The constructed MIMO antenna structure consumes a volume of 32 × 52 × 2 mm3.