报告题目：High Efficiency Wireless Communications towards 5G:
New Efficiency Enhancement Techniques from Circuit to System
报 告 人： 哈佛大学 张奥扬博士
报告时间： 2021年3月31日（周三）上午8：30-10：00
腾讯会议： ID：276 290 731
摘要：With the trend of increasing data throughput, modern wireless communications prefer high-spectral-efficiency modulations, which open lead to high peak to average power ratios. Large PAPR means that power amplifiers (PAs) need to operate in the power back-off (PBO) region most of the time. Therefore, enhancing power back-off efficiency is critical for achieving a high average power efficiency. In this talk we will discuss a proposed subharmonic switching (SHS) PA architecture that enhances PA/transmitter efficiency under large PAPR signals from RF range to mm-wave range to enable high efficiency wireless communications. Based on the proposed architecture, a phase-interleaved multi-SHS PA architecture is proposed to further enhance the efficiency while generating watt-level output power. In addition, to alleviate the large dynamic loss at higher frequency applications, we proposed a 5-6GHz current-mode SHS PA architecture to reduce conduction loss and minimize output impedance variation. To further improve the power efficiency in mm-wave communications, a 24-28GHz SHS Class E/F2,2/3 PA architecture with harmonic and subharmonic tuning is implemented to achieve efficiency enhancement at deep PBO.
报告人简介：
Dr. Aoyang Zhang received B.S. degree from Zhejiang University, Hangzhou, China, in 2014, and the Ph.D. degree from University of Southern California, Los Angeles in 2020, all in electrical engineering. He is currently a postdoctoral fellow at Harvard University.
His current research interests include threefold. First, analog/mixed signal/RF integrated circuits design including highly efficient power amplifiers for RF/millimeter wave applications, new circuit architectures for wireless communications and high-speed low-power data converters. Second, new circuit architecture with two-dimensional (2D) memristive devices, including black phosphorus and MoS2, to overcome technological limitations in computational complexity and power consumption. Third, scalable nuclear magnetic resonance (NMR) and electron spin resonance (ESR) integrated systems for quantum sensing, biotechnology, subsurface imaging. Dr. Zhang was the recipient of 2020-2021 IEEE Solid-State Circuits Society (SSCS) Predoctoral achievement award, Ming Hsieh Institute Scholar in 2020, IEEE SSCS Student Travel Grant Award (STGA) in 2018, Best Bachelor Thesis Award in 2014, and the first prize of Chinese National Mathematical Competition in 2010. From 2015 to present, he serves as a reviewer for IEEE Transactions on Circuits and Systems I/II (TCAS), IEEE Solid-State Circuits Letters (SSC-L), and IEEE Journal of Solid-State Circuits (JSSC).
