A New Envelope Predistorter With Envelope Delay Taps for Memory Effect Compensation

Author

Jung, Sung-chan ; Park, Hyun-chul ; Kim, Min-su ; Ahn, Gunhyun ; Van, Ju-ho ; Hwangbo, Hoon ; Park, Cheon-Seok ; Park, Sung-Kil ; Yang, Youngoo

Author_Institution

Sch. of Inf. & Commun. Eng., Sungkyunkwan Univ., Suwon

Volume

55

Issue

1

fYear

2007

Firstpage

52

Lastpage

59

Abstract

We present a new linearization method for high-power amplifiers, using an envelope predistorter (EPD) including envelope delay taps and control circuits, for memory effect compensation. The lower and upper third-order intermodulation (IM₃) components, generated by the EPD, can be separately controlled for their magnitudes and phases by the additional memory effect compensation circuits. By using experimental results for a high-power (30-W peak envelope power) class-AB amplifier, further linearity improvement was also demonstrated using the proposed EPD. For a two-tone signal with a tone spacing of 20 MHz, the proposed EPD, with only a single delay tap, cancelled the lower and upper IM₃ components by 20.84 and 18.17 dB, while the conventional EPD, with no envelope delay tap, cancelled them by 11.67 and 8.50 dB, respectively

Keywords

intermodulation distortion; linearisation techniques; power amplifiers; 20 MHz; ACLR; EPD; adjacent channel leakage power ratio; class-AB amplifier; envelop predistorter; envelope delay tap; high-power amplifiers; linear power amplifier; linearization method; memory effect compensation; Circuits; Delay effects; Energy consumption; High power amplifiers; Linearity; Modulation; Phase distortion; Power amplifiers; Power generation; Predistortion; Adjacent channel leakage power ratio (ACLR); envelope delay tap; envelope predistorter (EPD); linear power amplifier; linearity; memory effect;

fLanguage

English

Journal_Title

Microwave Theory and Techniques, IEEE Transactions on

Publisher

ieee

ISSN

0018-9480

Type

jour

DOI

10.1109/TMTT.2006.886909

Filename

4061050