Miniaturized Wearable Antennas with Improved Radiation Efficiency Using Magneto-dielectric Composites

Abstract

In this paper, two miniaturized flexible wearable antennas based on a planar dipole with a reflector are proposed and investigated. To realize miniaturization, the concept of magneto-dielectric (MD) composite materials was chosen. Numerical and experimental analyses were carried out to investigate the antenna performance (radiation efficiency, gain, and bandwidth) in the free space and on a tissue-equivalent phantom. Results demonstrated that MD composites are beneficial for wearable antenna miniaturization (up to 36%) and radiation efficiency improvement (up to 65% in free space and up to 23% on-body). Moreover, the antennas exhibit a low specific absorption rate.

KEYWORDS:

• Wearable antenna
• Flexible antenna
• Microstrip antenna
• Miniaturization
• Magneto-dielectric composite
• Antenna performance
• On-body performance
• Specific absorption rate
• Body-centric communications

Additional information

Funding

The authors would like to acknowledge the support of King Khalid University for this research through a grant RCAMS/KKU/003-16 under the Research Center for Advanced Materials Science at King Khalid University, Saudi Arabia and the University of Chemical Technology and Metallurgy, Sofia, Bulgaria.

Notes on contributors

Abdullah Al-Sehemi

Abdullah G Al-Sehemi is a professor in the Department of Chemistry King Khalid University, Saudi Arabia. He received his PhD from University of Leicester, UK. He is currently member of the Saudi Consultative Council. He was the dean of Scientific Research and director of The Research Center for Advanced Materials Science (RCAMS). He is an author of over 200 publications, co-inventor of several patents and the editor of 6 books. He is working experimentally and computationally in the field of advanced functional materials, nanomaterials, stereochemistry and drug design. Email: [email protected]

Ahmed Al-Ghamdi

Ahmed A Al-Ghamdi is a staff member at King Abdul Aziz University (KAU), Faculty of Science, Physics Department. He obtained his BSc in physics from KAU at 1981 and master degree in 1985 from Tulane University, USA. The PhD degree was obtained in 1990 from Sussex University, UK, in point defects created by ion implantation. He has 26 years of experience in academic and research activities in solid state physics. He worked in various field of solid physics applications including photodiodes, gas sensors, biosensors and various other field of applications. He is currently working in synthesis, characterization and applications in composites and nanocomposites. Email: [email protected]

Nikolay Dishovsky

Nikolay T Dishovsky received the PhD degree from the University of Chemical Technology and Metallurgy, Sofia, in 1983 and the Doctor of Science degree from the same university in 1997. Since 2000 he is a full professor and a head of the Department of Polymer Engineering at the University of Chemical Technology and Metallurgy. He is the author of 8 books, more than 230 articles and more than 45 patents for inventions. Prof Dishovsky was a recipient of the Bulgarian Patent Office award for the inventor of the year 2015. His research interests include fillers and filled elastomers, rubber-based nanocomposites, rubber-based sensors and microwave absorbers. Email: [email protected]

Nikolay Atanasov

Nikolay T Atanasov received the MSc and PhD degrees from the Technical University of Sofia, Sofia, Bulgaria, in 1999 and 2013, respectively. He is currently an associate professor with the Department of Communication and Computer Engineering, South-West University “Neofit Rilski”, Blagoevgrad, Bulgaria. His research interests include computational electrodynamics, SAR computation, and design of antennas for wireless devices, medical diagnostic and therapeutic applications of EM. He is particularly interested in the characterization of the electromagnetic properties of materials at microwave frequencies and investigation of the potential of conductive composites for antenna applications.

Gabriela Atanasova

Gabriela L Atanasova received the MSc and PhD degrees from the Technical University of Sofia, Sofia, Bulgaria, in 1999 and 2013, respectively. She is an associate professor with the Department of Communication and Computer Engineering, South-West University “Neofit Rilski”, Blagoevgrad, Bulgaria. Her research interests encompass theoretical and experimental studies for modeling interactions between EM fields and biological systems, as well as methods for the computer-aided analysis and design of high-frequency structures and antennas for body-centric communications, WLAN, WSN applications, etc. Email: [email protected], [email protected]