Experimental investigation of bias current and load modulation effects in phase distortion of GaN HEMTs

Author

Quaglia, R. ; Piazzon, L. ; Camarchia, Vittorio ; GiofreÌ€, R. ; Pirola, Marco ; Colantonio, P. ; Ghione, G. ; Giannini, F.

Author_Institution

Dept. of Electron. & Telecommun., Politec. di Torino, Turin, Italy

Volume

50

Issue

10

fYear

2014

fDate

May 8 2014

Firstpage

773

Lastpage

775

Abstract

The relationships between phase distortion, bias point and load modulation in power amplifiers are experimentally evaluated for two different GaN HEMT technologies. Measurements on devices with fixed and modulated load, to emulate the dynamic working conditions of the main stage of a Doherty amplifier, have been carried out through an advanced source/load-pull setup. Almost flat phase distortion against output power can be obtained by the proper bias point when the load remains constant, whereas it is shown that this possibility is not compatible with load modulation, inherently present in Doherty power amplifiers.

Keywords

III-V semiconductors; gallium compounds; high electron mobility transistors; power amplifiers; wide band gap semiconductors; Doherty power amplifiers; GaN; advanced source-load-pull setup; bias current; bias point; dynamic working conditions; fixed load; flat phase distortion; gallium nitride HEMT; load modulation effect; modulated load; phase distortion; power amplifiers; proper bias point;

fLanguage

English

Journal_Title

Electronics Letters

Publisher

iet

ISSN

0013-5194

Type

jour

DOI

10.1049/el.2014.0983

Filename

6824065