A Wearable Wideband Circularly Polarized Textile Antenna for Effective Power Transmission on a Wirelessly-Powered Sensor Platform

Abstract

In this communication, the simulation and experimental results of a novel wideband wearable circularly polarized textile antenna for low-power transmission in the 2.45 GHz ISM band are presented. The wide impedance and axial ratio bandwidths make it perfect for low microwave power transmission to a wearable sensor system. The antenna is flexible, robust and light weight so that it can be easily integrated into clothes. It is shown that the circularly polarized textile antenna has a 3-dB axial ratio bandwidth of 564 MHz (23%) and a <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">${-}10$</tex></formula> dB impedance bandwidth of 1086 MHz (44%) on a human body with the maximum gain of 4.9 dBic. Lastly, the textile antenna is employed on the battery-less temperature sensor system on a human arm to demonstrate the effective power transmission over a metre distance.