A gain/phase imbalance minimization technique for LINC transmitter

Author

Xuejun Zhang ; Nanawa, P. ; Larson, L.E. ; Asbeck, P.M.

Author_Institution

Center for Wireless Commun., California Univ., San Diego, La Jolla, CA, USA

Volume

2

fYear

2001

fDate

20-24 May 2001

Firstpage

801

Abstract

A simple calibration scheme for correction of the path imbalance in a LINC transmitter has been demonstrated. In this algorithm a baseband DSP evaluates the gain and phase imbalance with a set of calibration signals through a feedback loop. Compensation of path imbalance is accomplished within the DSP by introducing a pre-distortion term. The quadrature errors of the I/Q modulators set a limit on the overall performance of this algorithm. A prototype LINC system has been tested for CDMA IS95 baseband input and -38 dBc ACI was achieved.

Keywords

amplification; calibration; circuit feedback; compensation; minimisation; mobile radio; radio transmitters; ACI; CDMA IS95 baseband input; I/Q modulators; LINC transmitter; baseband DSP; calibration scheme; calibration signals; compensation; feedback loop; gain imbalance minimization technique; phase imbalance minimization technique; pre-distortion term; quadrature errors; Baseband; Broadband antennas; Calibration; Digital signal processing; Error correction; Feedback loop; High power amplifiers; Phase modulation; Transmitters; Wireless communication;

fLanguage

English

Publisher

ieee

Conference_Titel

Microwave Symposium Digest, 2001 IEEE MTT-S International

Conference_Location

Phoenix, AZ, USA

ISSN

0149-645X

Print_ISBN

0-7803-6538-0

Type

conf

DOI

10.1109/MWSYM.2001.967013

Filename

967013