Title :
A high-efficiency class-F GaN HEMT power amplifier with a diode predistortion linearizer
Author :
Ando, Akihiro ; Takayama, Yoichiro ; Yoshida, Tsuyoshi ; Ishikawa, Ryo ; Honjo, Kazuhiko
Author_Institution :
Univ. of Electro-Commun., Chofu
Abstract :
The class-F amplifier has high-efficiency, but shows specific distortion behavior. AM/AM and AM/PM characteristics of the series diode linearizer have been designed to cancel those of the class-F power amplifier by controlling the bias voltage and the bias feed resistance of the diode. With the diode predistortion linearizer, the IMD3 of the 1-watt 1.9-GHz class-F GaN HEMT power amplifier is improved by 4 dB over power outputs 6 to 23 dBm. The drain efficiency of the amplifier with the linearizer is not reduced that much. The diode linearizer has IMD3 asymmetry, and the effect of this on the linearization of the amplifier is discussed.
Keywords :
UHF amplifiers; UHF diodes; gallium compounds; high electron mobility transistors; power amplifiers; GaN; bias feed resistance; bias voltage; diode predistortion linearizer; drain efficiency; frequency 1.9 GHz; high-efficiency class-F HEMT power amplifier; power 1 W; Frequency; Gallium nitride; HEMTs; High power amplifiers; Nonlinear distortion; Power amplifiers; Power measurement; Predistortion; Schottky diodes; Voltage;
Conference_Titel :
Microwave Conference, 2008. APMC 2008. Asia-Pacific
Conference_Location :
Macau
Print_ISBN :
978-1-4244-2641-6
Electronic_ISBN :
978-1-4244-2642-3
DOI :
10.1109/APMC.2008.4958054
