Open Access

ARTICLE

Generation of OAM Waves and Analysis of Mode Purity for 5G Sub-6 GHz Applications

Shehab Khan Noor¹, Arif Mawardi Ismail¹, Mohd Najib Mohd Yasin^1,*, Mohamed Nasrun Osman¹, Nurulazlina Ramli², Ali H. Rambe³, J. Iqbal^4,5
1 Advanced Communication Engineering (ACE), Centre of Excellence, Faculty of Electronic Engineering Technology, Universiti Malaysia Perlis, Kangar, Perlis, Malaysia
2 Centre for Advanced Electrical & Electronic System (CAEES) Faculty of Engineering, Built Environment and Information Technology, SEGi University Petaling Jaya, Selangor, Malaysia
3 Department of Electrical Engineering, Universitas Sumatera Utara, Medan, 20155, Indonesia
4 School of Electrical and Electronic Engineering, Engineering Campus, Universiti Sains Malaysia, Nibong Tebal, 14300, Penang, Malaysia
5 Faculty of Engineering & Technology, Gomal University, 29050 kpk, Pakistan
* Corresponding Author: Mohd Najib Mohd Yasin. Email:

Computers, Materials & Continua 2023, 74(1), 2239-2259. https://doi.org/10.32604/cmc.2023.031170

Received 11 April 2022; Accepted 29 June 2022; Issue published 22 September 2022

Abstract

This article presents the generation of Orbital Angular Momentum (OAM) vortex waves with mode 1 using Uniform Circular Array (UCA) antenna. Two different designs, namely, UCA-1 (4-element array antenna) and UCA-2 (8-element array antenna), were designed and fabricated using FR-4 substrate to generate OAM mode 1 at 3.5 GHz (5G mid-band). The proposed antenna arrays comprised rectangular microstrip patch elements with inset fed technique. The elements were excited by a carefully designed feeding phase shift network to provide similar output energy at output ports with desired phase shift value. The generated OAM waves were confirmed by measuring the null in the bore sight of their 2D radiation patterns, simulated phase distribution and intensity distribution. The measurement results agree well with the simulation results. Moreover, a detailed mode purity analysis of the generated OAM waves was carried out considering different factors. The investigation found that the greater the number of elements, the higher the purity of the generated OAM wave. Compared with other previous works, the proposed antenna design of this paper is very simple to design and fabricate. In addition, the proposed antennas are compact in design even at lower frequency band with very wide bandwidth to meet the requirements of 5G mid-band applications.

---

Keywords

Orbital angular momentum; vortex waves; fifth generation wireless communications; uniform circular array antenna; patch antenna

---