Pattern reconfigurable dielectric resonator antenna using capacitor loading for internet of things applications

Pattern reconfigurable dielectric resonator antenna using capacitor loading for internet of things applications

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  International Journal ofElectrical and Computer Engineering (IJECE) Vol. 13, No. 4, August 2023, pp. 4145~4151 ISSN: 2088-8708, DOI: 10.11591/ijece.v13i4.pp4145-4151  4145 Journal homepage: http://ijece.iaescore.com Pattern reconfigurable dielectric resonator antenna using capacitor loading for internet of things applications Aymen Dheyaa Khaleel1 , Osman Ghazali1 , Aqeel Mahmood Jawad2 , Ayman Mohammed Ibrahim3 , Massudi Mahmuddin1 , Ahmed Jamal Abdullah Al-Gburi5 , Mohammad Najah Mahdi4 1 School of Computing, Universiti Utara Malaysia, Kedah, Malaysia 2 Department of Computer Technology Engineering, Al-Rafidain University College, Baghdad, Iraq 3 Ministry of Trade, Development of Private Sector Development, Baghdad, Iraq 4 Center for Telecommunication Research and Innovation, Faculty of Electronics and Computer Engineering, Universiti Teknikal Malaysia Melaka, Melaka, Malaysia 5 ADAPT Centre, School of Computing, Dublin City University, Dublin, Ireland Article Info ABSTRACT Article history: Received Jun 15, 2022 Revised Dec 12, 2022 Accepted Dec 16, 2022 This research study presents a cube dielectric resonator antenna (DRA) with four different radiation patterns for internet of things (IoT) applications. The various radiation patterns are determined by the grounded capacitor loading to reduce interference. The DRA is constructed of ceramic material with a dielectric constant of 30 and is fed via a coaxial probe located in the antenna’s center. Capacitors are used to load the four parasitic microstrip feed lines. Each pattern of radiation is adjustable by adjusting the capacitors loading on the feed line. The proposed antenna works at 3.5 GHz with -10 narrow impedance bandwidth of 74 MHz. Keywords: Capacitor loading Dielectric resonator antenna Internet of things Pattern agile antennas Pattern reconfigurable This is an open access article under the CC BY-SA license. Corresponding Author: Aymen Dheyaa Khaleel School of Computing, Universiti Utara Malaysia Sintok, 06010 Bukit Kayu Hitam, Kedah Kedah, Malaysia Email: a.dheyaa.khaleel@uum.edu.my 1. INTRODUCTION The internet of things (IoT) enables easy connectivity across a broad range of low-power wireless devices. Intelligent things are constantly detecting and collecting data from their surroundings [1]. Nowadays, increasingly more devices are connecting to the internet [2]. IoT technology enables almost all of these devices to operate wirelessly [3]. Therefore, in order to handle the enormous number of networked devices, it is crucial to design antennas that are effective for IoT applications. A dielectric resonator antenna (DRA) is one of the most efficient antennas being developed by researchers to lower the dissipated power since it requires less metal in the antenna construction [4]. One of its most desirable characteristics is that the DRA has minimal conductor loss or surface wave loss. [5], [6]. With feeding methods including probes, apertures, and microstrip lines, DRA is straightforward to operate. feeding system producing a variety of radiation patterns, including omnidirectional and directional radiation patterns [7]. By aiming the radiation pattern in a specified direction, pattern reconfigurable antennas may decrease interference and the average energy needed for packet transmission, lowering data collisions [8]. Almost all IoT applications work at the S-band frequency range and S-band refers to a frequency spectrum with a range of 2 to 4 GHz. This has several applications like Wi-Fi, industrial, scientific, and medical radio band (ISM band), LTE, and 5G [9]. Especially the channel for band 3.5 GHz for 5G-enabled IoT [10].
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   ISSN: 2088-8708 IntJ Elec & Comp Eng, Vol. 13, No. 4, August 2023: 4145-4151 4146 There are three types of reconfigurable antennas: polarization reconfigurable [11], frequency reconfigurable [12], and pattern reconfigurable [13]. The aim of a pattern reconfigurable antenna is to reduce interference by controlling the radiation pattern to radiate in desired directions. There are various methods for obtaining pattern reconfigurable in DRA. Some of these methods which researchers use are electrical change such as using a passed antenna array [14], passed array with switch, capacitor loading [15], [16], electrical switch PIN diodes [17], [18], multi-feed [19], [20], multi-port with switches [21], switches on slot in ground plane [22]. On the other hand, some of the researchers used mechanical change, such as liquid material as a dielectric resonator by changing the material inside the dielectric resonator by using a pump to get different radiation patterns [23]–[25], and the other researcher used a motor to rotate the antenna to steer the radiation pattern [26], [27]. The aim of this research study is to design a narrow band pattern reconfigurable dielectric resonator antenna that works at 3.5 GHz for 5G-enabled IoT. In this research study, the cube shape of the dielectric resonator consists of ceramic martial with a dielectric constant of 30. The dielectric resonator is fed by a probe feed from the middle bottom of the dielectric resonator. The dielectric resonator sits on an FR4 board which has a dielectric constant of 4.3. In addition, four direct microstrip feed lines were added to the dielectric resonator; these feeds are connected to the capacitor loading to the ground. When changing the value of the capacitor will get different radiation patterns. 2. METHOD In this research, the method to design the antenna is by using the TE111 modes of the dielectric waveguide model (DWM) [28]; the equations DWM are (1) to (3). 𝐾𝑧 = 𝜋 𝑎 ; 𝐾𝑦 = 𝜋 𝑏 (1) 𝐾𝑧 𝑡𝑎𝑛 ( 𝐾𝑧𝑑 2 ) = √(𝜀𝑟 − 1)𝐾° 2 + 𝐾𝑧 2 (2) 𝐾𝑥 2 + 𝐾𝑦 2 + 𝐾𝑧 2 = 𝜀𝑟𝐾° 2 (3) 𝐾° denotes the wavenumber in free space and the wavenumbers within the three directions 𝑥, 𝑦, and 𝑧 inside the dielectric resonator directions KX, KY, and KZ respectively. On the other hand, 𝜀𝑟 denotes the dielectric constant of the dielectric resonator material. Finally, a, b, and d denote the dimensions of the rectangle dielectric resonator. 2.1. The design of antenna The form of the suggested DRA is cube. The cube-shaped works the same as a rectangular shape dielectric resonator [29]. The dimensions of DRA are shown in Table 1, with the antenna’s complete dimensions and their values in millimeters. The antenna’s construction is made up of a dielectric resonator mounted on an FR-4 substrate. The substrate is made of FR-4 material, has a 4.3 dielectric constant, and is 1.6 mm thick. The FR-4 substrate is placed on top of the ground plane, which is 60 mm wide and long. The antenna was fed by a probe feed that was located in the bottom middle of the dielectric resonator. In addition, four microstrip feed lines with grounded capacitor loading are designed as shown in Figure 1. The structure of the antenna from the front view and side view is shown in Figures 1(a) and (b), respectively. Table 1. The dimensions of the antenna Parameters Description Abbreviations Value (mm) The width, length and height of the cube-shaped dielectric resonator Wd, Ld, and Hd 9.3 The width and the length of substrate and ground Wg and Lg 60 The thickness of ground plane Hg 0.035 The thickness of substrate Hs 1.6 The length of parasitic feed line inside the dielectric resonator Hf 2 Probe feed hole inside the dielectric resonator Lf 0.65 2.2. Capacitor loaded configurations Four parasitic microstrip feed lines feed the dielectric resonator from the four sides. Each parasitic microstrip feed line is loaded with a capacitor that is connected to a ground plane, as shown in Figure 1. Changing the values of these capacitors may get four cases. The capacitors configurations of all cases are
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  Int J Elec& Comp Eng ISSN: 2088-8708  Pattern reconfigurable dielectric resonator antenna using capacitor loading for … (Aymen Dheyaa Khaleel) 4147 tabulated in Table 2. Capacitor values for capacitors 1 through 4 in Case 1 are (0.01, 1, 1, 1) pF respectively, Capacitor values for capacitors 1 through 4 in Case 2 are (1, 0.01, 1, 1) pF for capacitors 1 to 4 respectively, Case 3 has capacitors with values of (1, 1, 0.01, 1) pF for capacitors 1 to 4 respectively, and Case 4 has capacitors with values of (1, 1, 1, 0.01) pF for capacitors 1 to 4 respectively. (a) (b) Figure 1. The structure of the antenna (a) front view and (b) side view Table 2. The dimensions of the antenna Cases Capacitor 1 (pF) Capacitor 2 (pF) Capacitor 3 (pF) Capacitor 4 (pF) Case 1 0.01 1 1 1 Case 2 1 0.01 1 1 Case 3 1 1 0.01 1 Case 4 1 1 1 0.01 3. RESULTS AND DISCUSSION The proposed antenna has four cases. These cases are changing the values of the grounded capacitor loading. These cases can obtain various radiation patterns. Figure 2 shows that the antenna’s reflection coefficient for all cases is -12.24 dB at 3.5 GHz, and the -10 dB impedance bandwidth is 74 MHz, with a frequency range of 3.48 to 3.56 GHz. Figure 3 shows a three-dimensional view of the radiation pattern at the resonance frequency of 3.5 GHz for case 1 in Figure 3(a), case 2 in Figure 3(b), case 3 in Figure 3(c), and case 4 in Figure 3(d). Each case instance thus has its own radiation pattern. The result shows the direction of the radiation pattern is opposite to the location of the capacitor loading with the value of 0.01 pF. The efficiency for all four cases almost has the same value efficiency as shown in Figure 4. Table 3 shows the comparison between all cases (1 to 4). All cases have the same band, directivity, gain, and efficiency, but each case has different directions of the radiation pattern. Figure 2. Reflection coefficient of the antennas for all cases
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   ISSN: 2088-8708 IntJ Elec & Comp Eng, Vol. 13, No. 4, August 2023: 4145-4151 4148 (a) (b) (c) (d) Figure 3. The radiation pattern view of the antenna at 3.5 GHz (a) case 1, (b) case 2, (c) case 3, and (d) case 4 Figure 4. The total efficiency for all the cases Table 3. The parameter for all cases Parameter Case 1 Case 2 Case 3 Case 4 -10 dB impedance bandwidth 74 MHz 74 MHz 74 MHz 74 MHz Directivity at 3.5 GHz 7.1 dBi 7.1 dBi 7.1 dBi 7.1 dBi Gain at 3.5 GHz 4.9 dB 4.9 dB 4.9 dB 4.9 dB Rad. Efficiency at 3.5 GHz 60% 60% 60% 60% Main lobe direction for Theta at Phi=0˚ 19.0˚ 0.0˚ -19.0˚ 0.0˚ Main lobe direction for Theta at Phi=90˚ 0.0˚ 19.0˚ 0.0˚ -19.0˚
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  Int J Elec& Comp Eng ISSN: 2088-8708  Pattern reconfigurable dielectric resonator antenna using capacitor loading for … (Aymen Dheyaa Khaleel) 4149 4. CONCLUSION A four-microstrip feed line loaded with a ground capacitor is implemented to dielectric resonator antenna fed by probe feed are successfully designed. This method yielded four unique radiation patterns. At a resonant frequency of 3.5 GHz, all four cases have a narrow -10 impedance bandwidth of 74 MHz, which is ideal for S-band narrow bandwidth applications such as the channel for band 3.5 GHz for 5G-enabled IoT. In the future, further study will be needed to establish the efficiency of this technique for antenna manufacturing. ACKNOWLEDGEMENTS We acknowledge the financial support from Al-Rafidain University College, Iraq, under the research fund, with reference number: RUC112022 for the support of this research. 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   ISSN: 2088-8708 IntJ Elec & Comp Eng, Vol. 13, No. 4, August 2023: 4145-4151 4150 [23] Z. Chen and H. Wong, “Wideband glass and liquid cylindrical dielectric resonator antenna for pattern reconfigurable design,” IEEE Transactions on Antennas and Propagation, vol. 65, no. 5, pp. 2157–2164, May 2017, doi: 10.1109/TAP.2017.2676767. [24] Z. Chen, J. Xiang, and H. Wong, “Pattern reconfigurable antenna with flowing liquid switch,” 2017 International Applied Computational Electromagnetics Society Symposium (ACES), pp. 1–2, 2017. [25] J. Ren et al., “Radiation pattern and polarization reconfigurable antenna using dielectric liquid,” IEEE Transactions on Antennas and Propagation, vol. 68, no. 12, pp. 8174–8179, Dec. 2020, doi: 10.1109/TAP.2020.2996811. [26] H. Fayad and P. Record, “Experimental investigation on new steerable dielectric resonator antenna,” Electronics Letters, vol. 43, no. 19, 2007, doi: 10.1049/el:20071820. [27] C. Biancotto and P. Record, “Conical steerable dielectric resonator antenna,” Electronics Letters, vol. 44, no. 19, 2008, doi: 10.1049/el:20081840. [28] R. K. Mongia and A. Ittipiboon, “Theoretical and experimental investigations on rectangular dielectric resonator antennas,” IEEE Transactions on Antennas and Propagation, vol. 45, no. 9, pp. 1348–1356, 1997, doi: 10.1109/8.623123. [29] A. Petosa, Dielectric resonator antenna handbook. Artech House Publishers, 2007. BIOGRAPHIES OF AUTHORS Aymen Dheyaa Khaleel Al-Obaidi currently is a postdoctoral researcher at UUM School of Computing, Universiti Utara Malaysia, Kedah, Malaysia. He received his B.Sc. in computer communication engineering in 2009, from Al-Rafidain University College, Baghdad, Iraq. In 2013, he received an M.Sc. in electrical engineering from Universiti Tenaga Nasional (UNITEN), Kajang, Malaysia. In 2019, he received a Ph.D. in electrical, electronics, and systems engineering from Universiti Kebangsaan Malaysia (UKM), Faculty of Engineering and Built Environment, Department of Electrical, Electronics, and Systems Engineering. His current research interests in antenna and propagation and wireless communication. He can be contacted at a.dheyaa.khaleel@uum.edu.my. Osman Ghazali received his Bachelor of Information Technology, Master of Science in information technology, and Ph.D. in information technology (computer network) from Universiti Utara Malaysia in 1994, 1996, and 2008 respectively. He is actively pursuing research and supervising postgraduate students in the area of cloud computing and computer networks. His research interests include ad-hoc networks, cloud computing, network security, layered multicast, network performances, network traffic engineering, packet error correction, wireless and mobile networks, and video streaming. He can be contacted at email: osman@uum.edu.my. Aqeel Mahmood Jawad received his B.Sc. in computer and communication engineering from Al-Rafidain University College, Iraq in 2009, his M.Sc. in electrical engineering from Universiti Tenaga Nasional (UNITEN), Malaysia, 2013, and his Ph.D. degree in communication engineering from Universiti Kebangsaan Malaysia (UKM), Malaysia, in 2021, and a degree with the Department of Electrical, Electronics and Systems Engineering, Faculty of Engineering and Built Environments, Universiti Kebangsaan Malaysia. He is with the Department of Computer Techniques Engineering, Al-Rafidain University College, Baghdad-Iraq, as a lecturer and a head of the communication lab. His research interests include wireless communications, transmutation line and digital communication, satellite communications theory, energy-efficient wireless power transfer, WPT charging applications based on Unmanned aerial vehicle (UAV) techniques, advanced mathematics, and wireless sensor networks applications. He can be contacted at email: aqeel.jawad@ruc.edu.iq. Ayman Mohammed Ibrahim received his B.Sc. in computer engineering from Baghdad University, Iraq, in 1997. He received his master’s in computer engineering from Baghdad University, Iraq, in 2003. He received his Ph.D. in computer engineering from Universiti Teknikal Malaysia Melaka (UTeM), Malaysia, in 2021. His research interests include control systems, fuzzy control, artificial intelligence, machine learning, steganography, and MIMO antenna. He can be contacted at ayman971972@gmail.com.
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  Int J Elec& Comp Eng ISSN: 2088-8708  Pattern reconfigurable dielectric resonator antenna using capacitor loading for … (Aymen Dheyaa Khaleel) 4151 Massudi Mahmuddin obtained his Ph.D. in 2010 in the areas of system engineering at Cardiff University, United Kingdom. He is currently a Dean of the Student Affairs Department, Universiti Utara Malaysia (UUM). During the last 20 years of his services at the school, teaching, research, and development interests have been in the areas of the technical and social aspects of network computing, computational intelligence, and expert systems. Seeking an ultimate understanding of computing’s ecosystem and human well-being is the direction of interest. He can be contacted at ady@uum.edu.my. Ahmed Jamal Abdullah Al-Gburi received his M.Eng. and Ph.D. degrees in Electronics and Computer Engineering (Telecommunication systems) from Universiti Teknikal Malaysia Melaka (UTeM), Malaysia, in 2017 and 2021, respectively. He is currently a postdoctoral fellow with the Microwave Research Group (MRG), Faculty of Electronics and Computer Engineering, UTeM. He has authored and co-authored a number of journals and proceedings. His research interests include electromagnetic bandgap (EBG), artificial magnetic conductors (AMC), frequency selective surfaces (FSS), UWB antennas, array antennas, and small antennas for UWB and 5G applications. He has received the Best Paper Award from the IEEE Community and won a number of gold, silver, and bronze medals in international and local competitions. He can be contacted at ahmedjamal@utem.edu.my. Mohammed Najah Mahdi Al-Niamey received his B.Sc. degree in Information Engineering, College of Engineering, Baghdad University, Iraq, in 2002, and his M.Sc. in Information Technology from the Faculty of Computer Science and Information Technology, University of Malaya (UM) in 2011. He later obtained his Ph.D. in Information and Communication Technology, in 2017. He is currently a Post-Doctoral Researcher at the University Tenaga Nasional (UNITEN) Malaysia. His research interests include faceted search, information overload, exploratory search, machine learning, python/machine learning, data scientist, internet of things (IoT), 5G, software engineering. and information retrieval. He can be contacted at mohammed.mahdi@adaptcentre.ie.