Design of a flexible waterproof antenna for Internet of Things applications

Abstract

We propose a new broadband flexible waterproof antenna suitable for Internet of Things applications. The antenna is comprised of three components: radiating elements fed by a 50-Ω coplanar waveguide transmission line and two layers from an elastomer composite (used as a substrate and top encapsulation) which completely covers the antenna's radiating elements to provide water and dust resistance. An antenna prototype is fabricated and tested. Experimental and numerical results show that the proposed antenna has broad bandwidth (|S₁₁| ≤ −10 dB) over the frequency range of 0.83–2.52 GHz, high radiation efficiency of about 92% and good radiation patterns. The antenna was also immersed into water for 10 s, 10, 30 and 60 min, respectively and reflection coefficient magnitudes were measured, to verify its waterproof capability. The durability and flexibility tests were performed on the antenna prototype. Results show that there is no significant degradation in the antenna performance.

KEYWORDS:

• Waterproof antenna
• flexible antenna
• antenna for IoT

Acknowledgements

This work was supported by the King Khalid University, Research Center for Advanced Materials Science at King Khalid University, Kingdom of Saudi Arabia under Grant # RCAMS/KKU/005-19.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by King Khalid University: [Grant Number # RCAMS/KKU/005-19].

Notes on contributors

Abdullah G. Al-Sehemi

Abdullah G. Al-Sehemi is a Professor in the department of chemistry King Khalid University, Saudi Arabia. He received his Ph.D. 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 the author of over 200 publications, co-inventor of several patents and the editor of six books. He is working experimentally and computationally in the field of advanced functional materials, nanomaterials, stereochemistry, and drug design.

Ahmed A. 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 on 1985 from Tulane University, USA. The Ph.D. degree was obtained on 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.

Nikolay T. Dishovsky

Nikolay T. Dishovsky received the Ph.D. 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 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.

Nikolay T. Atanasov

Nikolay T. Atanasov received the M.Sc. and Ph.D. 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. He is also Head of Testing Laboratory of Electromagnetic Compatibility in Bulgarian Institute of Metrology, Sofia, Bulgaria. His research interests include computational electrodynamics, SAR computation, design of antennas for wireless devices, medical diagnostic and therapeutic applications of EM. He is particularly interested in characterization of the electromagnetic properties of materials at microwave frequencies and investigation of potential of conductive composites for antenna applications.

Gabriela L. Atanasova

Gabriela L. Atanasova received the M.Sc. and Ph.D. degrees from the Technical University of Sofia, Sofia, Bulgaria, in 1999 and 2013, respectively. She currently is an Associate Professor with the Department of Communication and Computer Engineering and Vice-Dean for the Faculty of Engineering, South-West University 'Neofit Rilski', Blagoevgrad, Bulgaria. Her research interests encompass theoretical and experimental studies for modelling interactions between EM fields and biological systems, as well as methods for the computer-aided analysis and design of high-frequency structures and antennas.