A predistorter for a power amplifier affected by the even-order distortion [W-CDMA base station applications]

Author

Hongo, Naoki ; Miyatani, Tetsuhiko ; Akaiwa, Yoshihiko

Author_Institution

Yagi Memorial Telecommun. Syst. Lab., Hitachi Kokusai Electr. Inc, Miyagi, Japan

Volume

1

fYear

2003

fDate

6-9 Oct. 2003

Firstpage

266

Abstract

The even-order distortion at baseband perturbs bias conditions of a power amplifier (PA), and creates a new odd-order distortion, which shows a hysteresis effect on AM-AM and AM-PM characteristics. This effect combined with the original odd-order distortion generates imbalanced inter modulation distortion (IMD) outside of the signal bandwidth, which depends on frequency separation. The imbalanced IMD limits the compensation performance of conventional predistorters. We propose a new predistorter for W-CDMA base stations. The predistorter compensates the distortion to less than 60 dBc, even if the PA is affected by even-order distortion. The PA model and the adaptive algorithm are also shown.

Keywords

code division multiple access; hysteresis; intermodulation distortion; linearisation techniques; power amplifiers; AM-AM; AM-PM; IMD; PA bias conditions; W-CDMA base stations; baseband even-order distortion; frequency separation; hysteresis effect; imbalanced inter modulation distortion; linearization techniques; memory effect; odd-order distortion; power amplifier predistorter; predistorter compensation performance; Adaptive algorithm; Bandwidth; Base stations; Baseband; Distortion; Frequency; Hysteresis; Multiaccess communication; Power amplifiers; Signal generators;

fLanguage

English

Publisher

ieee

Conference_Titel

Vehicular Technology Conference, 2003. VTC 2003-Fall. 2003 IEEE 58th

ISSN

1090-3038

Print_ISBN

0-7803-7954-3

Type

conf

DOI

10.1109/VETECF.2003.1285020

Filename

1285020