Simple and Flexible Structure of Dual-band Monopole Wearable Patch Antenna

Abstract

A dual-band monopole antenna with a simple, flexible structure designed for wearable applications is proposed in this paper. These antennas are expected to perform with the least amount of degradation in vicinity to the human body. To meet these requirements, the wearable antenna design becomes challenging. Moreover, human body has high dielectric permittivity and losses that significantly affect the desired antenna performance, especially causing the detuning. Thus, a dual-band wearable antenna is projected to cater a solution to this problem. The proposed antenna of 35 mm X 36 mm has a compact size and designed on a flexible jeans material substrate. The antenna resonating at 2.8 GHz and 3.8 GHz provides dual band operation over 2.68 GHz- 2.95 GHz and 3.65 GHz-4.18 GHz which claims its application in WiMAX. The SAR measured is well within the standard limits even without incorporating the structures to mitigate back radiation. The obtained specific absorption rate (SAR) values at lower and higher resonating frequencies are 1.50 W/kg and 1.59 W/kg respectively without back radiation prevention structure. Furthermore, a technique to calibrate the antenna structure for mitigating the moisture effect in the textile fabric is proposed. The proposed antenna asserts its place under on-body communication as it offers all the traits essential for a wearable antenna.