This research work addresses the problem of mutual coupling between the antenna elements for ultra wideband diversity applications. A novel H‐type decoupling structure has been proposed which successfully suppresses the mutual coupling by 7 to 10 dB as compared to the nondecoupled radiating elements. The decoupling structure has been tested for shared and isolated ground planes. The isolation between the antennas was measured to be more than 25 dB in most of the band. The feasibility of the proposed structure in diversity applications has been analyzed by measuring the envelope correlation coefficient which was found out to be less than −30 dB. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2715–2720, 2013

This article reports the impact of using an ordinary adhesive material to bond a dielectric resonator antenna (DRA) to the ground plane to predict the potential variations in resonant frequency and impedance bandwidth of DRA. A set of aperture fed and monopole fed cylindrical DRAs have been analyzed at resonant frequencies of 2.4 and 8.9 GHz. For DRAs resonating at 2.4 GHz, an upward resonance frequency shift of 6.2% along with increase of 1.4 to 2% in impedance bandwidth have been observed. However, a significant shift of 12% in the resonant frequency and 17–20% increase in impedance bandwidth have been observed for DRAs operating at 8.9 GHz. End‐fire TM01 mode has been excited in the DRAs, and it has been observed that the adhesive material has not affected the operating resonant mode. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1502–1506, 2014

A patterns diversity slot antenna loaded with a dielectric resonator is presented for on‐body communication systems in 2.45 GHz band. The diversity is achieved by launching even and odd modes on coplanar feed lines resulting in end‐fire and broadside radiation pattern respectively. Loading of dielectric resonator enhances impedance bandwidth and improves isolation between broadside and end‐fire patterns. A common impedance bandwidth of 4% is obtained along with ports isolation of 22 dB. Diversity gain is calculated for three unique on‐body channels and the maximum diversity gain of 8.5 dB is achieved for nonline‐of‐sight on body channel. Large diversity gain and planar geometry makes this antenna suitable for various on‐body communication applications.

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A high‐temperature tolerant pattern diversity antenna is presented for body wearable applications in hostile conditions. The proposed system consists of a dielectric resonator antenna (DRA) placed at the centre of a slot loop antenna. The combination yields pattern diversity with broadside and endfire radiation patterns from slot loop and DRAs, respectively. The antenna system offers common bandwidth of 4.95% with port isolation of better than 13 dB at 2.4 GHz. The thermal characteristics of antenna have been studied for high‐temperature operation and no discernible change in the radiation behaviour is noted. The antenna undergoes 2% resonant frequency shift when operated at elevated temperature. The antenna diversity has been measured for three on‐body communication channels. The antenna offers 9.5 dB diversity gain in a pure non‐line‐of‐sight channel surrounded by a rich fading environment subjected to the selection combining scheme. The antenna has dimensions of 0.4λo × 0.4λo × 0.1λo.