A New Wideband Distributed Doherty Amplifier for WCDMA Repeater Applications

Author

Lee, Yong-Sub ; Lee, Mun-Woo ; Kam, Sang-Ho ; Jeong, Yoon-Ha

Author_Institution

Dept. of Electron. & Electr. Eng., Pohang Univ. of Sci. & Technol., Pohang, South Korea

Volume

19

Issue

10

fYear

2009

Firstpage

668

Lastpage

670

Abstract

A new wideband distributed Doherty amplifier (WDDA) for wideband code division multiple access (WCDMA) repeater applications is reported. The distributed structure provides wideband performance while not needing an N-way splitter and combiner. The two-stage Doherty amplifiers achieve high gain and high efficiency. Also, the linearity of the WDDA is improved by the post-distortion using gate bias optimization of the Doherty amplifiers. For verification, the proposed WDDA is implemented using GaN HEMTs and tested with a one-carrier WCDMA signal at 2.14 GHz. From the measured results at an average output power of 36 dBm (10 dB back-off power), the WDDA shows an adjacent channel leakage ratio (ACLR) of - 45 dBc at plusmn 5 MHz offset with a total gain over 24 dB and a total power-added efficiency over 15% over a 160 MHz bandwidth.

Keywords

III-V semiconductors; broadband networks; code division multiple access; distributed amplifiers; gallium compounds; high electron mobility transistors; radio repeaters; wideband amplifiers; GaN; HEMTs; N-way splitter; WCDMA repeater applications; adjacent channel leakage ratio; bandwidth 160 MHz; frequency 2.14 GHz; gate bias optimization; wideband code division multiple access; wideband distributed Doherty amplifier; Adjacent channel leakage ratio (ACLR); Doherty amplifier; distributed amplifier; efficiency; wideband code division multiple access (WCDMA);

fLanguage

English

Journal_Title

Microwave and Wireless Components Letters, IEEE

Publisher

ieee

ISSN

1531-1309

Type

jour

DOI

10.1109/LMWC.2009.2029755

Filename

5233763