High Isolation Compact Four Port MIMO Antenna with Slotted Ground for UWB Applications

Abstract

This research article has proposed a compact coplanar waveguide fed four-element ultra-wide-band (UWB) multi-input-multi-output (MIMO) antenna accompanying high isolation (S <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">21</inf> < −17dB) and good return loss characteristics (S <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</inf> < −10dB). The proposed antenna operates in the entire UWB range (3.1–10.6 GHz) and is also useful for 3.5/5 GHz WLAN and Wi-MAX applications. The proposed antenna comprises four identical radiating elements, a unique asymmetric staircase ground structure, and an L-shaped stub are stacked to achieve good return loss characteristics and also good impedance matching in the entire UWB band. The proposed antenna is incorporated an orthogonal arrangement to achieve the required isolation among the four radiating elements. As a result, the overall size of the intended UWB-MIMO antenna acquired 50 × 50 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> dimensions which are printed on the highly available FR-4 substrate (ε <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">r</inf> = 4.4) with a thickness of 1.6 mm. The performance of the proposed MIMO antenna is thoroughly studied in terms of diversity parameters, where it has been found that ECC < 0.02 with an acceptable channel capacity loss < 0.6 bps/Hz and the other parameters DG, MEG, TARC have been evaluated and presented as well.