High Speed Dynamic Bias Switching Power Amplifier for OFDM Applications

Author

Cha, Jukyung ; Jun, Youngsang ; Nam, Sangwook

Author_Institution

Samsung Thales, Yongin

fYear

2008

fDate

27-31 Oct. 2008

Firstpage

1683

Lastpage

1686

Abstract

An efficiency-enhanced power-amplifier system using dynamic bias switching method is presented. The presented system generates two different voltage sources from one source for drain bias of a RF power amplifier. The drain of the RF power amplifier is biased at low voltage level while the input RF signal is detected to be small. The drain bias is rapidly changed to high voltage level when the input RF signal reaches a certain threshold level. The measured drain bias at V_H state is 4.6V with the efficiency of the bias switching system, 49% and at V_L is 2.94V with 86%. The measured result shows that the overall efficiency of the proposed RF power amplifier is improved by 62% compared to that of the fixed bias amplifier, when OFDM signal with bandwidth 8.46MHz is applied.

Keywords

OFDM modulation; power amplifiers; bandwidth 8.46 MHz; drain bias; dynamic bias switching; orthogonal frequency division multiplexing; power amplifiers; voltage 2.94 V; voltage 4.6 V; High power amplifiers; Low voltage; OFDM; Power amplifiers; Power generation; Power measurement; Radio frequency; Radiofrequency amplifiers; Switching systems; Threshold voltage;

fLanguage

English

Publisher

ieee

Conference_Titel

Microwave Conference, 2008. EuMC 2008. 38th European

Conference_Location

Amsterdam

Print_ISBN

978-2-87487-006-4

Type

conf

DOI

10.1109/EUMC.2008.4751798

Filename

4751798