Far-Field Wireless Power Transmission: RF, Signal and System Designs

Bruno Clerckx is a Reader (Associate Professor) in the Electrical and Electronic Engineering Department at Imperial College London (London, United Kingdom). He received his M.S. and Ph.D. degree in applied science from the Université catholique de Louvain (Louvain-la-Neuve, Belgium) in 2000 and 2005, respectively. From 2006 to 2011, he was with Samsung Electronics (Suwon, South Korea) where he actively contributed to 3GPP LTE/LTE-A and IEEE 802.16m and acted as the rapporteur for the 3GPP Coordinated Multi-Point (CoMP) Study Item. Since 2011, he has been with Imperial College London, first as a Lecturer (2011-2015), then as a Senior Lecturer (2015-2017), and now as a Reader. From March 2014 to March 2016, he also occupied an Associate Professor position at Korea University, Seoul, Korea.

He also held visiting research appointments at Stanford University, EURECOM, National University of Singapore and The University of Hong Kong. He is the author of 2 books, 140 peer-reviewed international research papers, 150 standard contributions and the inventor of 75 issued or pending patents among which 15 have been adopted in the specifications of 4G (3GPP LTE/LTE-A and IEEE 802.16m) standards. Dr. Clerckx served as an editor for IEEE TRANSACTIONS ON COMMUNICATIONS from 2011-2015 and is currently an editor for IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS. He is an Elected Member of the IEEE Signal Processing Society SPCOM Technical Committee. His research area is communications and signal processing for wireless networks.

Paul Mitcheson, is Professor of Electrical Energy Conversion at Imperial College London and a member of the Control and Power Group where he leads the Wireless Power Lab.  He has a team of 11 researchers working within a portfolio of £2M of active grants and is a member of the Executive Committee of the EPSRC Centre for Power Electronics (EP/K035304/1) where he has responsibility for outreach. He has expertise in high frequency WBG power electronics for resonant converters where a recent focus is in wireless power delivery for EVs and other applications including dynamic charging.

Multi-MHz resonant gate drives have recently been demonstrated.  He also has interests in LED driving and in energy harvester power electronics.  He has collaborations with UC Berkeley, University of Bologna and Huazhong University of Science and Technology. His research has been sponsored by EPSRC, the EC, EDF Energy and the UK Government.  His group has recently won the GaN Systems Future Power Challenge, and paper awards at IEEE Wireless Power Transfer Conference 2015 and ‘16 and the IEEE Workshop on Emerging Technologies 2015.  He recently appeared on the BBC demonstrating MHz wireless power and several of his patents on high frequency power electronics have been transferred to Drayson Technologies Ltd.

Abstract

This tutorial reviews some recent promising approaches to make far-field wireless power transmission (WPT) closer to reality. In contrast with talks/papers commonly given/published by the microwave/antenna community and the communication/signal processing community that separately emphasize RF, circuit and antenna solutions for WPT on one hand and communications, signal and system designs for WPT on the other hand, this tutorial uniquely bridges antenna, RF, signal and system designs in order to bring those communities closer to each other and get a better understanding of the fundamental building blocks of an efficient WPT network architecture.

We start by reviewing the engineering requirements and design challenges of making radiative wireless power a reality. We then review the state-of-the-art in antenna and RF design for WPT. We highlight similarities and difference with wireless communications. We identify limitations of current approaches and make critical observations before providing some fresh new look and promising avenues on signal and system designs for WPT. This will be the first time that a course covering RF, signal and system design for WPT will be presented at EuCAP.

Course Outline

This is a 3-hour tutorial with a 30min break in the middle.

1. Overview of WPT Technologies (20min)
   1. History of Microwave Wireless Power Transfer
   2. Microwave Wireless Power Transfer: A Fresh New Look
2. Rectenna design: Antenna and Rectifier perspectives (20min)
   1. Rectifier topologies
   2. Impedance matching challenges
3. Analytical model of a rectenna (30min)
   1. Antenna model
   2. Rectifier and diode models
4. Single-user WPT (20min)
   1. Energy beamforming
   2. Channel acquisition
   3. Extension and future work
5. Multi-user WPT (20min)
   1. WPT network architecture
   2. Power region characterization
   3. Extension and future work
6. Waveform design (30min)
   1. Effect of rectifier non-linearity
   2. Single-user waveform design
   3. Multi-user waveform design
   4. Circuit evaluations
   5. Extension and future work
7. Prototyping and Experimentation of WPT (20min)
   1. Experimental setup
   2. Output power processing requirements
   3. Results
8. Further discussions (20min)
   1. Safety and health issues
   2. Massive MIMO and mmwave WPT
   3. Joint design with wireless communications