A technique for the maintenance of FET power amplifier efficiency under backoff

Author

Geller, B.D. ; Assal, F.T. ; Gupta, R.K. ; Cline, P.K.

Author_Institution

COMSAT Lab., Clarksburg, MD, USA

fYear

1989

fDate

13-15 June 1989

Firstpage

949

Abstract

An operational technique for FET power amplifiers which allows the maintenance of high efficiency as the amplifier is backed off from its rated output power level is described. Using this technique, an experimental single-state 1-W C-band amplifier, capable of 65% power-added efficiency at its rated output power, maintains a minimum efficiency of 55% for a 10-dB output backoff range. Comparable amplifiers operating under conventional Class B or Class A demonstrate efficiencies of about 18% and 4%, respectively. An analytic basis for the technique is given. Experimental results are also presented for a three-stage, 2-W C-band amplifier.<>

Keywords

MMIC; field effect integrated circuits; microwave amplifiers; power amplifiers; power integrated circuits; 1 W; 2 W; 55 percent; 65 percent; C-band amplifier; FET power amplifier efficiency; backoff; output power level; power-added efficiency; three-stage amplifier; Degradation; FETs; High power amplifiers; Laboratories; Operational amplifiers; Phased arrays; Power amplifiers; Power generation; Radio frequency; Voltage;

fLanguage

English

Publisher

ieee

Conference_Titel

Microwave Symposium Digest, 1989., IEEE MTT-S International

Conference_Location

Long Beach, CA, USA

Type

conf

DOI

10.1109/MWSYM.1989.38879

Filename

38879