Analysis of Wearable Metamaterial-Based Ultrawide Band Antenna for Wireless Body Area Network

This paper introduces a wearable ultra-wideband (UWB) antenna designed for wireless body area network (WBAN) applications. The antenna utilizes a jeans substrate, making it ideal for wearable purposes. The substrate dimensions are 30 mm <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\times \mathbf{25}$</tex> mm with a thickness of 1.1 mm. The dielectric constant and loss tangent of the jeans textile are 1.7 and 0.025, respectively. The antenna operates within the 3 GHz to 10 GHz frequency range, characteristic of ultra-wideband antennas. A metamaterial structure is incorporated to enhance performance. The antenna's performance is assessed based on the reflection coefficient <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(\mathbf{S}_{\mathbf{11}})$</tex>, gain, efficiency, and radiation pattern. The metamaterial structure, operating in the 3 GHz to 10 GHz frequency range, is constructed using FR-4 material, which exhibits negative permittivity and permeability. The performance of the ultra-wideband (UWB) antenna is compared with and without the metamaterial structures. The antenna's performance is also evaluated when attached to the human body. Results demonstrate that the antenna's gain increases up to 4.8 dB when a metamaterial structure is added in front of the UWB antenna, and the efficiency improves from 82% to 87.02%. Additionally, the communication link between the wearable metamaterial antenna worn on the body and the base station is investigated.