RF Hardware Design for 5G mm-Wave and 6G Revolutions: Challenges and Opportunities
The fifth-generation (5G) mobile network technologies promise to deliver 10-Gbps peak data rate for 5G eMBB (enhanced Mobile Broadband) applications, sub-1ms latency and ultra-reliability for 5G mMTC (ultra-reliable machine type communication), and massive network capacity with increased availability to enable IoE (Internet-of-Everything) with x100 more wireless connected devices compared to 4G for 5G mMTC (massive machine type communication). To accomplish these challenging goals, it is imperative to move up from the sub-6 GHz 5G FR1 band to the millimeter-wave (mm-Wave) 5G FR2 band (i.e., 24.25 to 52.6 GHz). For example, 5G eMBB applications must use the 5G FR2 band to support numerous users with very high data rates in high-density urban areas, while also reducing the total cost and improving energy efficiency. However, the hardware requirements for mm-Wave 5G are putting serious pressures on the 5G hardware design communities.
Since the 5G FR2 band is ~ 4 to 75 times higher in frequency compared to the FR1 band, the power-added efficiency (PAE) of a 5G mm-Wave power amplifier (PA) will be considerably lower, making the mm-Wave PA a critical component and a very challenging barrier to low-power mm-Wave 5G. The mm-Wave 5G also presents some practical problems on the design of handsets and wireless infrastructures with multiple-input multiple-output (MIMO) antennas, as well as broadband modulated signal bandwidth, which demand wideband electronics, stringent linearity and effective beamsteering. Mm-Wave 5G MIMO systems also have considerably more PAs, RF switches, phase-shifter, low-noise-amplifiers (LNAs) and/or filters integrated in the RF front-end modules (FEMs) to achieve beamsteering to compensate for the path loss and blocking effects, making the performance and cost of these FEM hardware critical for the success of 5G mm-Wave consumer applications. The performance and cost of the RF hardware become even more essential and challenging as the industry evolves into the AI-centric 6G technologies that utilize Tera Hertz (THz) communications to achieve 1-Tbps peak data rate (i.e., x100 faster than 5G), with x10 reduced latency and x10 more connected devices than 5G.
In this talk, I will start with an introduction of the key 5G and 6G technology delivery goals, followed by a more detailed discussions on the hardware capabilities required for 5G mm-Wave applications. These may cover the hardware requirements on ultra-broadband mm-Wave fixed “last-mile” links, mobile handsets, mesh-enabled radios, base stations and small cells that can all contribute to reaching commercial 5G viability and open ultra-high-bandwidth low-latency applications in mobile virtual reality, robotics, automated manufacturing, etc. I would attempt to translate the requirements for some of these driver applications into hardware needs for mm-Wave 5G and also briefly for 6G, such as on the desired improvements in power efficiency, linearity, semiconductor technologies, and integration techniques.
Donald Y. C. Lie received his B.S.E.E. degree from the National Taiwan University in 1987, and the M.S. and Ph.D. in electrical engineering (minor in applied physics) from Caltech, Pasadena, in 1990 and 1995, respectively. He held technical and managerial positions at companies such as Rockwell International, Silicon-Wave (now Qualcomm), IBM, Microtune, and is currently the Keh-Shew Lu Regents Chair Professor in the Department of Electrical and Computer Engineering, Texas Tech University (TTU), an Adjunct Professor in the Department of Surgery, Texas Tech University Health Sciences Center (TTUHSC). He is also appointed as a Chair Professor, College of Electrical Engineering, National Chiao-Tung University (NCTU), Hsin-Chu, Taiwan, since 2018. He was a Visiting Lecturer to the ECE Department, University of California, San Diego (UCSD) during 2002-2007 and co-supervised Ph.D. students. He and his students have won 17 Best Paper Awards and authored over 230 peer-reviewed technical papers and book chapters with three TOP 100 most downloaded papers in IEEE Xplore™ and he holds seven U.S. patents. Dr. Lie is currently serving on the Executive or Steering Committees of the IEEE RFIC Symp., SiRF, MWSCAS, and TSWMCS (Texas Wireless Symp.), and on the Advisory Committee for IEEE VLSI-DAT. Dr. Lie has been awarded with 7 DARPA contracts at TTU, and has been serving on the IEEE 5G Technology Roadmap Hardware Technical Working Group (TWG). He is a Fellow of IEEE, a Senior Chapter Member of the National Academy of Inventors (NAI), and a member of ASCO (American Society of Clinical Oncology). His research interests are: (1) power-efficient 5G/6G mm-Wave/RF/Analog IC and system design; and (2) interdisciplinary/clinical research on medical electronics, biosensors and oncology.