Open Access

ARTICLE

Higher Order OAM Mode Generation Using Wearable Antenna for 5G NR Bands

by Shehab Khan Noor¹, Arif Mawardi Ismail¹, Mohd Najib Mohd Yasin^1,*, Mohamed Nasrun Osman¹, Thennarasan Sabapathy¹, Shakhirul Mat Salleh², Ping Jack Soh³, Ali Hanafiah Rambe⁴, Nurulazlina Ramli⁵

1 Advanced Communication Engineering (ACE), Centre of Excellence, Faculty of Electronic Engineering & Technology, Universiti Malaysia Perlis, Kangar, Perlis, Malaysia
2 Faculty of Engineering Technology (FTK), Department of Electronic Engineering Technology, Universiti Malaysia Perlis (UniMAP), Unicity Alam Campus, 02100, Padang Besar, Perlis, Malaysia
3 Centre for Wireless Communications (CWC), University of Oulu, 90570, Oulu, Finland
4 Department of Electrical Engineering, Universitas Sumatera Utara, Medan, 20155, Indonesia
5 Centre for Advanced Electrical and Electronic System (CAEES) Faculty of Engineering, Built Environment and Information Technology, SEGi University Selangor, Malaysia

* Corresponding Author: Mohd Najib Mohd Yasin. Email:

Computer Systems Science and Engineering 2023, 47(1), 537-551. https://doi.org/10.32604/csse.2023.037381

Received 01 November 2022; Accepted 13 January 2023; Issue published 26 May 2023

Abstract

This paper presents a flexible and wearable textile array antenna designed to generate Orbital Angular Momentum (OAM) waves with Mode +2 at 3.5 GHz (3.4 to 3.6 GHz) of the sub-6 GHz fifth-generation (5G) New Radio (NR) band. The proposed antenna is based on a uniform circular array of eight microstrip patch antennas on a felt textile substrate. In contrast to previous works involving the use of rigid substrates to generate OAM waves, this work explored the use of flexible substrates to generate OAM waves for the first time. Other than that, the proposed antenna was simulated, analyzed, fabricated, and tested to confirm the generation of OAM Mode +2. With the same design, OAM Mode −2 can be generated readily simply by mirror imaging the feed network. Note that the proposed antenna operated at the desired frequency of 3.5 GHz with an overall bandwidth of 400 MHz in free space. Moreover, mode purity analysis is carried out to verify the generation of OAM Mode +2, and the purity obtained was 41.78% at free space flat condition. Furthermore, the effect of antenna bending on the purity of the generated OAM mode is also investigated. Lastly, the influence of textile properties on OAM modes is examined to assist future researchers in choosing suitable fabrics to design flexible OAM-based antennas. After a comprehensive analysis considering different factors related to wearable applications, this paper demonstrates the feasibility of generating OAM waves using textile antennas. Furthermore, as per the obtained Specific Absorption Rate (SAR), it is found that the proposed antenna is safe to be deployed. The findings of this work have a significant implication for body-centric communications.

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Keywords

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