Split Slant-End Stubs for the Design of Broadband Efficient Power Amplifiers

  • Park, Youngcheol (Department of Electronics Engineering, Hankuk University of Foreign Studies) ;
  • Kang, Taeggu (Department of Electronics Engineering, Hankuk University of Foreign Studies)
  • Received : 2015.12.04
  • Accepted : 2016.01.08
  • Published : 2016.01.31


This paper suggests a class-F power amplifier with split open-end stubs to provide a broadband high-efficiency operation. These stubs are designed to have wide bandwidth by splitting wide open-end stubs into narrower stubs connected in shunt in an output matching network for class-F operation. In contrast to conventional wideband class-F designs, which theoretically need a large number of matching lines, this method requires fewer transmission lines, resulting in a compact circuit implementation. In addition, the open-end stubs are designed with slant ends to achieve additional wide bandwidth. To verify the suggested design, a 10-W class-F power amplifier operating at 1.7 GHz was implemented using a commercial GaN transistor. The measurement results showed a peak drain efficiency of 82.1% and 750 MHz of bandwidth for an efficiency higher than 63%. Additionally, the maximum output power was 14.45 W at 1.7 GHz.


Broadband;Class-F;Efficiency;Power Amplifier


Supported by : Hankuk University of Foreign Studies


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