volume | PIER Journals

Abstract

This study investigates the performance of a dipole antenna above electromagnetic bandgap (EBG) substrateswith different number of patchesto realize a low specific absorption rate (SAR) antenna for a 4G wireless communications system (3.5GHz band). A cubic head model is used fortheinitialanalysis toestimate the radiation characteristics and the SAR of the antenna. Computational results have shown that the antenna above anEBG substrate could provide a maximum reduction of 81% in the SAR and a radiation efficiency improvement of 10% when compared with theantenna above a perfect electric conductor (PEC) ground plane.However, the antenna above an EBG substrate with a lower number of patches results in a higher resonance frequency and cannot provide sufficient SAR reduction.In both the cubic and realistic head models,a similar tendency was observedin the SAR reduction capability ofthe antenna above the EBG substrates whencompared with the antenna above the PEC ground plane. For therealistic head model, the SARs of the dipole above EBGsubstrateswith 20 or 24 EBG patches can be reduced by 16% when compared to the casewith 12or16EBG patches.The variability of the SAR in the operating frequency band (|S_{1110 dB) of the antennais 5-35% for different EBG substrates.}

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Dr. Ryo Ikeuchi

Dr. Kwok Hung Chan

Prof. Akimasa Hirata