Tutorial 1
RF energy harvesting and wireless power transfer systems: antenna designs and challenges
Tutorial Organizers
Dr. Nasimuddin (I2R, Singapore)
Dr. Mohammad Hashmi (Nazarbayev University, Kazakhstan)
Abstract and Scope
Global demand for energy has grown rapidly in recent years. To meet the long-term demand for global energy, different techniques of wireless energy harvesting have been introduced. Harvesting RF energy is an alternative solution, especially with the advances and popularity of wireless communication devices. These communication devices are constantly transmitting RF energy, so RF energy harvesting paves a way to utilize the abundant scattered electromagnetic (EM) waves in our surrounding environment. The available EM waves (RF energy) can be in any polarization, such as elliptical, linear, or circular. By using an appropriate receiving antenna, EM waves can be converted into electrical energy for low-powered devices, and thus, there is much focus put toward RF energy-harvesting (RFEH) systems, especially in receiving antenna designs. A receiving circularly polarized antenna enables the system to harvest RF energy regardless of the device orientation, as well as making the system insensitive to polarization loss. The RF waves/energy that is found in the surrounding area can exist in any orientation/polarization, so dual circularly polarized antennas or dual polarized antennas are more desirable for energy harvesting systems. The first part of tutorial talk will elaborate on all these aspects and recent advancements in the antenna technologies for RFEH systems. The compact and low-profile circularly polarized antenna designs will also be presented in detail for RFEH system demonstrations.
Furthermore, the emergence of low power sensor nodes and biomedical applications has necessitated the requirements of seamless battery charging techniques. Apparently, these functionalities can be facilitated by wireless power transfer (WPT) technology. The WPT assists users to rid of inconvenient wires and facilitates powering and charging the devices’ batteries. The WPT systems have the potential to bring a complete turnaround in a variety of applications. They have been lately employed in a number of segments such as biomedicine, consumer electronics, low-power deceives, and wireless technologies. WPT can be broadly classified as far- (radiative) and near-field (non-radiative) types. Over the last decades, there has been an increase in the employment of near-field WPT systems in a variety of evolving applications that demand miniature and robust wireless end modules (i.e., resonating antennas). One such emerging application is found in biomedicine, where WPTs are critical due to their ability to charge implants without the use of inconvenient and unsafe cables. This clearly calls for the design and realization of a small-size WPT capable of coping with the low-power regime. To cater to the requirements of such applications, the exploitation of the slotted ground plane (SGP)-based WPT systems has recently piqued interest. In general, the SGP method allows reducing the resonator area, resulting in the realization of ultra-compact WPTs. Apparently, the existing multiple challenges of SGP-type WPTs necessitate efficient trade-offs for the best achievable outcome. The second part of tutorial talk will take the audience through the fundamentals of near-field WPT systems to the advanced design techniques and associated applications.
Biography
Dr Nasimuddin (M’2003-SM’2009) received his B.Sc. degree in 1994 from Jamia Millia Islamia, India, and his M.Tech. (Microwave Electronics) and Ph.D. degrees in 1998 and 2004, respectively, from the University of Delhi, India. Dr Nasimuddin worked as a Senior Research Fellow (1999-2003) on a DST sponsored project and a CSIR grant, Senior Research Fellow in Engineering Science at the Department of Electronic Science, University of Delhi, India. He has worked as an Australian Postdoctoral Research Fellow (2004-2006) being awarded a Discovery project grant from the Australian Research Council at Macquarie University, Australia. Currently, he is working as a scientist III at the Institute for Infocomm Research, A*STAR, Singapore. He has published 225 journal and conference technical papers on microstrip-based microwave antennas and components. Three US/SG patents have been granted and four filed on leaky wave/RF energy harvesting/circularly polarized/grid antenna technologies. He has edited two books and contributed a chapter to a book “Microstrip antennas” published in 2011. His research interests include multi-layered microstrip-based structures, antenna system research and development. Dr Nasimuddin is a Senior Member of the IEEE and the IEEE Antennas and Propagation Society. He was awarded a Senior Research Fellowship from the CSIR, India in Engineering Science (2001-2003); a Discovery Projects Fellowship from the Australian Research Council (2004-2006); Singapore Manufacturing Federation Award (with project team) in 2014, the Young Scientist Award from the International Union of Radio Science (URSI) in 2005, and Exceptional Performance Reviewer Award Certificate from the IEEE Antennas and Propagation Society in 2019. He is an Associate Editor of the IEEE Open Journal of Antennas and Propagation, Frontiers in Antennas and Propagation, and International Journal of Antennas and Propagation. He is an editorial broad member for various antennas/microwave/RF related journals. He has been a member of the organizing committees of several Antenna and Propagation related conferences, including IEEE APS 2021, serving as Publication Chair/Publicity Chair/Conference Secretary. He was the Chair of IEEE Singapore MTT/AP Joint Chapter (2021-2022).
Mohammad S. Hashmi received the B.Tech. degree from Aligarh Muslim University, India, the M.S. degree from the Darmstadt University of Technology, Germany, and the Ph.D. degree from Cardiff University, Cardiff, U.K in 2001, 2004, and 2009 respectively. He had held research and engineering positions with the University of Calgary, Canada, Cardiff University, U.K., Thales Electronics GmbH, Germany, and Philips Technology Center, Germany. He previously served as tenured professor at IIIT Delhi, India. Now, he is faculty at the Department of Electrical and Computer Engineering, Nazarbayev University, Kazakhstan. He is also the PI of the RF Circuits and Antenna Characterization Laboratory at Nazarbayev University. His research activities have led to one book, 3 book chapters, three patents (1 US patent awarded, and 2 pending), and over 250 peer-reviewed journal and conference publications. He was recipient of Visvesvaraya Young Faculty Research Fellow from MEITY, Government of India, ARFTG Microwave Measurement Fellowship and his authored/co-authored papers have won multiple best paper awards at leading IEEE conferences such as IMS 2009, MWSCAS 2016 and 2021, ECTC 2019, IMPACT 2014 and 2022, and EAI Conference IoTaaS 2022. He was also the MTT-11 innovative design competition winner at IEEE IMS 2008 held in Atlanta. His team also won the filter design competitions held during the IEEE MTT-S flagship conference IMaRC 2015 and 2017. His current research interests include the design of advanced RF circuits, antenna structures for near-field wireless power transfer, and high-and low-frequency instrumentation. He was an Associate Editor for IEEE Microwave Magazine, and serves as Review Editor for Frontiers in Antennas and Propagation.
Tutorial 2
Antenna for 5G and 6G systems
Tutorial Organizers
A Alphones (Nanyang Technological University)
Abstract and Scope
The fifth-generation (5G) technology has been rolled out in the beginning of this decade. This technology can support any spectrum ranging from 400 MHz to 90 GHz. The 5G systems will mainly use two frequency bands, namely Sub-6 GHz (below 6 GHz) and millimeter wave (above 24 GHz) besides sub 1 GHz band. The 5G frequency bands used in various countries under three categories: licensed, shared, and existing. The Sub-6 GHz band has better geographical coverage than the millimetre wave band as the lower frequency signals can easily penetrate buildings/obstacles. Another advantage of using a Sub-6 GHz band is that it can be easily installed alongside
existing 4G long term evolution (LTE) infrastructure. Seeing the evolution of each generation by every decade, the next evolution targeted is 6G system which is expected to be around 2030. Hence the antennas to be used for various applications like hand held devices, wearable electronics, IoT systems, Satellite and automotive radar systems need to be designed to meet the specifications and standards dictated by the 5G/6G wireless community. This tutorial will provide guidelines and few design approaches of the above systems.
Biography
A Alphones received his B.Tech. from Madras Institute of Technology in 1982, M.Tech. from Indian Institute of Technology Kharagpur in 1984 and Ph.D. degree in Optically Controlled Millimeter wave Circuits from Kyoto Institute of Technology (Japan) in 1992. He was a JSPS visiting fellow from 1996-97 at Japan. During 1997-2001, he was with Centre for Wireless Communications, National University of Singapore involved in the research on optically controlled passive/active devices. Since 2001 he is Professor with the School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore. He has 35 years of research experience. He has published and presented over 320 technical papers in peer reviewed International Journals/ Conferences. His current interests are electro-magnetic analysis on planar RF circuits and integrated optics, microwave photonics, visible light communication and positioning, metamaterial based leaky wave antennas and wireless power transfer technologies. He was involved many IEEE flagship conferences held in Singapore and General Chair of APMC 2009, MWP 2011, TENCON 2016 and APMC 2019. He was the chairman of IEEE Singapore section during 2015-2016, 2018, 2023 and a senior member of IEEE. He is Singapore representative of IEICE(Japan).He is also the panel member of IEEE Conference Application Review Committee.
Tutorial 3
Fully Symmetrical Planar Mercator Smith Chart: A Web Mapping Approach for Microwave Active and Passive Circuits
Tutorial Organizers
Dr. Hemant Kumar (NIT Tiruchirappalli)
Abstract and Scope
To design and develop any microwave active and passive circuits and components such as impedance matching circuits for microwave amplifiers, mixers, oscillators, etc., there are generally two approaches to be followed namely: the analytical approach and the graphical approach. In this proposed study, a novel graphical approach will be discussed in detail. In RF/Microwave engineering, the Smith chart is a graphical measuring tool that is used to design, analyse, and develop RF/Microwave circuits and components. The 2D conventional Smith Chart has a few drawbacks, including the inability to plot negative resistance parameters and whole reactance curves within a finite space, and even if the point with negative resistance can be mapped back into the unit circle by taking the mirror image, the fact that it shares the same space as the impedances with positive resistance parts is not aesthetically appealing. In 2011, a 3D Smith Chart based on Riemann Sphere was proposed. Although this approach successfully plots positive and negative resistance and whole reactance curves onto a finite 3D surface, it relies on CAD software to use as a design tool or visualization aid for RF and microwave community.
To overcome the above-mentioned limitations, a Planar Mercator Smith Chart (PMSC) is proposed based on the principle of Mercator projection. The PMSC elegantly represents all the resistance and reactance on a 2D flat surface in a fully symmetrical way to reveal the internal symmetries of positive resistance and reactance to their corresponding negative values. The web mapping features such as “Loxodromes” are used to create the VSWR and/or constant reflection coefficient magnitude scales. The longitudes are Mercator projected as vertical lines perpendicular to the equator and are used for the scales of reflection coefficient angle, wavelength toward the generator, and/or load. This eliminates the need for CAD software to use it as a design tool or visualization aid, unlike 3D Smith Chart, and it may be a useful graphical chart for solving microwave problems involving any type of load. A few of the design problems, such as one-port microwave oscillator load-matching circuit, stub matching, etc., will be discussed, which will be utilizing the topological properties of Mercator projection of the proposed PMSC to solve and analyse the microwave circuits.
Biography
Dr. Hemant Kumar (M’18-SM’21, IEEE) obtained his B.Tech. (Honors) in ECE from Kurukshetra University in 2010 and Ph.D. in Electrical Engineering from IIT Bombay in 2018. He has worked on various consultancy projects sponsored by government organizations and private industries during his Ph.D. at IIT Bombay. He has been rewarded twice for his commendable engagement as a teaching assistant for the course “Antennas” offered through MOOCs, NPTEL, IIT Bombay. He has delivered many guest lectures and invited talks in the field of Antennas and Microwave Circuits in various FDP/STTP/QIP programs. Currently, He is working as an Assistant Professor in the Department of Electronics and Communication Engineering at NIT Tiruchirappalli. His research interests include electromagnetics, antennas, microwave passive circuits, monopulse radar, and microwave imaging. He has published many research articles in reputed national/international journals and conferences, and filed one patent and copyright. He is serving as one of the Editors of the IETE Journal of Research. He is also a reviewer in a number of national/international journals, including IEEE, IET, IETE, etc. He is a senior member of IEEE, a life member of IETE, ATMS, and IEI.
