Distortion-cancellation of GaAs-HBT amplifier using bias-voltage droop control

Author

Chung, Yueh-Ting

Author_Institution

Freescale Semicond. Inc., Tempe, AZ, USA

Volume

48

Issue

18

fYear

2012

Firstpage

1134

Lastpage

1136

Abstract

Presented is a simple design method to improve the linearity of (heterojunction) bipolar junction transistor (HBT or BJT) power amplifiers (PAs) designed in the class-AB or B mode. The introduced approach controls the dynamic drooping characteristic of the base-emitter DC bias-voltage of HBTs as input power increases, resulting in correcting the nonlinear AM-AM and AM-PM conversions. Measurements for the demonstrated single-stage GaAs-HBT PAs with 29 dBm saturated output power show 6.5 dB improvement in the adjacent channel power ratio (ACPR) at 15 dBm average output power and 0.6 dB increase of the linear output power where the ACPR crosses -40 dBc.

Keywords

gallium arsenide; heterojunction bipolar transistors; power amplifiers; voltage control; ACPR; BJT; GaAs; PA; adjacent channel power ratio; base-emitter DC bias-voltage; bias-voltage droop control; bipolar junction transistor; class-AB mode; class-B mode; distortion-cancellation; dynamic drooping characteristic; heterojunction junction transistor; nonlinear AM-AM conversions; nonlinear AM-PM conversions; power amplifiers; single-stage-HBT PA;

fLanguage

English

Journal_Title

Electronics Letters

Publisher

iet

ISSN

0013-5194

Type

jour

DOI

10.1049/el.2012.1832

Filename

6294560