A digital Doherty transmitter suitable for wireless infrastructure efficiency enhancement

Author

Darraji, Ramzi ; Ghannouchi, Fadhel M.

Author_Institution

Dept. of Electr. & Comput. Eng., Univ. of Calgary, Calgary, AB, Canada

fYear

2011

fDate

8-10 Sept. 2011

Firstpage

151

Lastpage

154

Abstract

The present work proposes a digital Doherty power amplifier (PA) with improved efficiency performance. The efficiency enhancement is achieved by using a digital adaptive phase alignment mechanism that is implemented to address the problem of power-dependent phase imbalance between the carrier and peaking cells of gallium-nitride (GaN) Doherty PAs following the turn-on of the peaking cell. An average efficiency of 57% has been measured using a one-carrier Worldwide Interoperability for Microwave Access (WiMAX) signal with a peak-to-average power ratio of 7 dB. This corresponds to an improvement of 7% in average efficiency with no linearity degradation compared to a conventional single-input fully analog Doherty PA.

Keywords

WiMax; power amplifiers; GaN; WiMAX signal; carrier cells; digital Doherty power amplifier; digital Doherty transmitter; digital adaptive phase alignment mechanism; linearity degradation; microwave access; one-carrier worldwide interoperability; peaking cells; power-dependent phase imbalance; single-input fully analog Doherty PA; wireless infrastructure efficiency enhancement; Computer architecture; Degradation; Gallium nitride; HEMTs; Power amplifiers; Power generation; Wireless communication; Doherty power amplifier; GaN; digital signal processing; dual-input architecture; power efficiency;

fLanguage

English

Publisher

ieee

Conference_Titel

Mediterranean Microwave Symposium (MMS), 2011 11th

Conference_Location

Hammamet

ISSN

2157-9822

Print_ISBN

978-1-4577-1814-4

Electronic_ISBN

2157-9822

Type

conf

DOI

10.1109/MMS.2011.6068550

Filename

6068550