中国物理B ›› 2015, Vol. 24 ›› Issue (5): 58401-058401.doi: 10.1088/1674-1056/24/5/058401

• INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY • 上一篇    下一篇

Analysis of the third harmonic for class-F power amplifiers with an I–V knee effect

赵博超a, 卢阳a, 魏家行b, 董梁b, 王毅a, 曹梦逸a, 马晓华b, 郝跃a   

  1. a Key Laboratory of Wide Band-Gap Semiconductor Materials and Devices, School of Microelectronics, Xidian University, Xi'an 710071, China;
    b School of Advanced Materials and Nanotechnology, Xidian University, Xi'an 710071, China
  • 收稿日期:2014-07-04 修回日期:2014-12-01 出版日期:2015-05-05 发布日期:2015-05-05

Analysis of the third harmonic for class-F power amplifiers with an I–V knee effect

Zhao Bo-Chao (赵博超)a, Lu Yang (卢阳)a, Wei Jia-Xing (魏家行)b, Dong Liang (董梁)b, Wang Yi (王毅)a, Cao Meng-Yi (曹梦逸)a, Ma Xiao-Hua (马晓华)b, Hao Yue (郝跃)a   

  1. a Key Laboratory of Wide Band-Gap Semiconductor Materials and Devices, School of Microelectronics, Xidian University, Xi'an 710071, China;
    b School of Advanced Materials and Nanotechnology, Xidian University, Xi'an 710071, China
  • Received:2014-07-04 Revised:2014-12-01 Online:2015-05-05 Published:2015-05-05
  • Contact: Hao Yue E-mail:yhao@xidian.edu.cn
  • About author:84.30.Le; 84.40.DC; 85.30.Tv; 61.72.uj

摘要: The appearance of third-generation semiconductors represented by gallium nitride (GaN) material greatly improves the output power of a power amplifier (PA), but the efficiency of the PA needs to be further improved. The Class-F PA reduces the overlap of drain voltage and current by tuning harmonic impedance so that high efficiency is achieved. This paper begins with the principle of class-F PA, regards the third harmonic voltage as an independent variable, analyzes the influence of the third harmonic on fundamental, and points out how drain efficiency and output power vary with the third harmonic voltage with an I–V knee effect. Finally, the best third harmonic impedance is found mathematically. We compare our results with the Loadpull technique in advanced design system environment and conclude that an optimized third harmonic impedance is open in an ideal case, while it is not at an open point with the I–V knee effect, and the drain efficiency with optimized third harmonic impedance is 4% higher than that with the third harmonic open.

关键词: class-F power amplifier, third harmonic, I–, V knee effect, Loadpull technique

Abstract: The appearance of third-generation semiconductors represented by gallium nitride (GaN) material greatly improves the output power of a power amplifier (PA), but the efficiency of the PA needs to be further improved. The Class-F PA reduces the overlap of drain voltage and current by tuning harmonic impedance so that high efficiency is achieved. This paper begins with the principle of class-F PA, regards the third harmonic voltage as an independent variable, analyzes the influence of the third harmonic on fundamental, and points out how drain efficiency and output power vary with the third harmonic voltage with an I–V knee effect. Finally, the best third harmonic impedance is found mathematically. We compare our results with the Loadpull technique in advanced design system environment and conclude that an optimized third harmonic impedance is open in an ideal case, while it is not at an open point with the I–V knee effect, and the drain efficiency with optimized third harmonic impedance is 4% higher than that with the third harmonic open.

Key words: class-F power amplifier, third harmonic, I–V knee effect, Loadpull technique

中图分类号:  (Amplifiers)

  • 84.30.Le
84.40.Dc (Microwave circuits) 85.30.Tv (Field effect devices) 61.72.uj (III-V and II-VI semiconductors)