A positive feedback pilot system for a wide bandwidth feedforward amplifier

Author

Braithwaite, R. Neil ; Hunton, Matthew J.

Author_Institution

Powerwave Technol., Santa Ana, CA, USA

fYear

2010

fDate

28-30 Sept. 2010

Firstpage

1778

Lastpage

1781

Abstract

The positive feedback pilot system described in for controlling the second loop of a feedforward (FF) compensated power amplifier (PA) is improved for use in wide bandwidth applications. The log-detector and limiter are replaced with an automatic level controller (ALC) making the control of the pilot shut-off threshold more precise. A multi-pilot frequency optimization is proposed, which when combined with the pilot shut-off feature, allows for wide bandwidth cancellation of distortion without introducing discernible pilot residuals in the output signal. Test results on a feedforward power amplifier show that the multi-pilot optimization improves the wide bandwidth cancellation by 5 dB over that of a single pilot.

Keywords

feedback amplifiers; feedforward amplifiers; power amplifiers; automatic level controller; feedforward compensated power amplifier; limiter; log-detector; multipilot frequency optimization; pilot shut-off threshold; positive feedback pilot system; wide bandwidth cancellation; wide bandwidth feedforward amplifier; Bandwidth; Distortion measurement; Feedforward neural networks; Frequency measurement; Nonlinear distortion; Optimization; Power amplifiers; Amplifier distortion; power amplifier linearization;

fLanguage

English

Publisher

ieee

Conference_Titel

Microwave Conference (EuMC), 2010 European

Conference_Location

Paris

Print_ISBN

978-1-4244-7232-1

Type

conf

Filename

5616968