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-This paper presents design and specific absorption rate analysis of a 2.4 GHz wearable patch antenna on a conventional and electromagnetic bandgap (EBG) ground planes, under normal and bent conditions. Wearable materials are used in the design of the antenna and EBG surfaces. A woven fabric (Zelt) is used as a conductive material and a 3 mm thicker Wash Cotton is used as a substrate. The dielectric constant and tangent loss of the substrate are 1.51 and 0.02 respectively. The volume of the proposed antenna is 113×96.4×3 mm 3 . The metamaterial surface is used as a high impedance surface which shields the body from the hazards of electromagnetic radiations to reduce the Specific Absorption Rate (SAR). For on-body analysis a three layer model (containing skin, fats and muscles) of human arm is used. Antenna employing the EBG ground plane gives safe value of SAR (i.e. 1.77W/kg<2W/kg), when worn on human arm. This value is obtained using the safe limit of 2 W/kg, averaged over 10g of tissue, specified by the International Commission of Non Ionization Radiation Protection (ICNIRP). The SAR is reduced by 83.82 % as compare to the conventional antenna (8.16 W/kg>2W/kg). The efficiency of the EBG based antenna is improved from 52 to 74 %, relative to the conventional counterpart. The proposed antenna can be used in wearable electronics and smart clothing.

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In this paper, four different models of a 2.4 GHz flexible microstrip patch wearable antenna are designed and analyzed. The basic geometry of the radiating element of the antennas is a rectangular patch and is backed by conventional, mushroom‐type, slotted, and spiral electromagnetic band gap (EBG) ground planes. A 3‐mm‐thick wash cotton textile is used as a substrate material in the design of the antennas as well as EBG surfaces. An electro‐textile (Zelt) is used as a conductive material for the proposed antennas. The performance of these antennas is analyzed in terms of return loss, gain, bandwidth efficiency, and specific absorption rate (SAR) using Computer Simulation Technology Microwave Studio (CST MWS). The designed antennas are further investigated for on and off body conditions under normal and bent states. The experimental results show that the antennas radiate with an adequate gain (5.72‐7.3 dB), bandwidth (65.43‐103.1 MHz), and efficiency (55.51%‐74.04%), depending on the type of the ground plane used. The antenna backed by the mushroom‐type EBG gives the smallest value of SAR (1.79 W/kg < 2 W/kg), which makes it a suitable candidate for body worn applications in the unlicensed industrial, scientific, and medical (ISM) band.