Specific absorption rate analysis of a WLAN antenna using mushroom-type electromagnetic bandgap (EBG) structure

This paper presents the SAR (Specific Absorption Rate) analysis of a metamaterial-based 2.4 GHz patch antenna. Wearable material (Velcro) is used as a substrate in the design of the proposed antenna and EBG surface. For comparison purpose a conventional patch is used as a reference antenna. Velcro is used as a substrate material in the design of the reference antenna. A human arm is modeled to conduct the on-body SAR analysis. The proposed and reference antennas are alternatively worn on human arm to analyze and compare their return loss, radiation patterns, gain, directivity, efficiency and SAR. The SAR averaged over the 10 g of tissue, is obtained. The value of SAR is 4.63 W/kg for the conventional patch antenna which is beyond the safe level of 2 W/kg according to European IEC Standard. A Mushroom like Metamaterial surface is used as a ground plane in the design of the proposed antenna due to which the SAR is reduced from 4.63 W/kg to 1.02 W/kg. The 77.9% reduction in SAR provides a basis for the proposed antenna to be used in safer wearable applications. Simulations are accomplished in CST MWS.