ZTE Communications ›› 2022, Vol. 20 ›› Issue (S1): 22-26.DOI: 10.12142/ZTECOM.2022S1004

• Research Paper • Previous Articles     Next Articles

Derivative-Based Envelope Design Technique for Wideband Envelope Tracking Power Amplifier with Digital Predistortion

YI Xueya1, CHEN Jixin1, CHEN Peng1, NING Dongfang2, YU Chao1()   

  1. 1.State Key Laboratory of Millimeter Waves, Southeast University, Nanjing 210096, China
    2.ZTE Corporation, Shenzhen 518057, China
  • Online:2022-01-25 Published:2022-03-01
  • About author:YI Xueya received the B.E. degree in electronic and information engineering from Xidian University, China in 2018. She is currently pursuing the M.E. degree in electromagnetic fields and microwave technology at the State Key Laboratory of Millimeter Waves, Southeast University, China. Her current research interests include bandwidth reduction and shaping of envelope and digital predistortion for wideband envelope tracking power amplifiers.|CHEN Jixin received the B.S. degree in radio engineering from Southeast University, China in 1998, and the M.S. and Ph.D. degrees from Southeast University in 2002 and 2006, respectively, all in electromagnetic field and microwave technique. Since 1998, he has been with the State Key Laboratory of Millimeter Waves, Southeast University. He is currently a professor with the School of Information Science and Engineering and Director of the Department of Electromagnetic Field and Microwave Engineering. His research interests include microwave and millimeter-wave circuit design and monolithic microwave integrated circuit (MMIC) design. Dr. CHEN is the winner of 2016 Keysight Early Career Professor Award and 2016 National Natural Science Prize Second Prize. He has served as TPC Chair of RFIT2019, and TPC Co-Chair of HSIC2012 and UCMMT2012.|CHEN Peng received the B.E. degree in communication engineering and the M.E. degree in electronic engineering from Harbin Institute of Technology, China in 2010 and 2012, respectively, and the Ph.D. degree in electronic engineering from University College Dublin, Ireland in 2016. From 2017 to 2020, he was a research associate with Centre for High Frequency Engineering, Cardiff University, UK. Since 2020, he has been with the State Key Laboratory of Millimeter Waves and is currently a lecturer with the School of Information Science and Engineering, Southeast University, China. His current research interests include the design and optimization of high-efficiency power amplifiers.|NING Dongfang received the M.S. and Ph.D. degrees in control science and engineering from Northwestern Polytechnical University, China in 2016 and 2019. He is currently a senior RF algorithm architect in ZTE Corporation, working in nonlinear system behavioral modeling and linearization for wireless and RF systems.|YU Chao (chao.yu@seu.edu.cn) received the B.E. degree in information engineering, the M.E. degree in electromagnetic fields and microwave technology from Southeast University (SEU), China in 2007 and 2010, respectively, and the Ph.D. degree in electronic engineering from University College Dublin, Ireland in 2014. He is currently a professor with the State Key Laboratory of Millimeter Waves, School of Information Science and Engineering, SEU. His research interest includes microwave and millimeter wave power amplifier modeling and linearization, and 5G massive MIMO RF system design.
  • Supported by:
    the National Natural Science Foundation of China (NSFC)(62022025);the Natural Science Foundation of Jiangsu Province(BK20200065);ZTE Industry-University-Institute Cooperation Funds(HC-CN-20191121016)

Abstract:

A novel envelope design for an envelope tracking (ET) power amplifier (PA) based on its derivatives is proposed, which can trade well off between bandwidth reduction and tracking accuracy. This paper theoretically analyzes how to choose an envelope design that can track the original envelope closely and reduce its bandwidth, and then demonstrates an example to validate this idea. The generalized memory polynomial (GMP) model is applied to compensate for the nonlinearity of ET PA with the proposed envelope design. Experiments are carried out on an ET system that is operated with the center frequency of 3.5 GHz and excited by a 20 MHz LTE signal, which show that the proposed envelope design can make a good trade-off between envelope bandwidth and efficiency, and satisfactory linearization performance can be realized.

Key words: bandwidth reduction, envelope tracking, shaping function, supply modulator