Improved convergence of fractionally-spaced constant modulus equalisers in presence of noise

Author

Skowratananont, K. ; Lambotharan, S. ; Chambers, J.A.

Author_Institution

Dept. of Electr. Eng., Imperial Coll. of Sci., Technol. & Med., London, UK

Volume

34

Issue

17

fYear

1998

fDate

8/20/1998 12:00:00 AM

Firstpage

1644

Lastpage

1646

Abstract

The constant modulus algorithm (CMA) applied to a fractionally spaced equaliser, with length and zero constraints on the channel, has been shown to be globally convergent when there is no channel noise. However, in the presence of channel noise, the performance of the CMA can suffer because of the existence of undesired local minima corresponding to different delays. A new technique is introduced, based on the Gram-Schmidt orthogonalisation, to obtain convergence to an optimum delay where the mean square error is minimum

Keywords

adaptive equalisers; adaptive signal processing; convergence of numerical methods; covariance matrices; delays; filtering theory; interference suppression; least mean squares methods; Gram-Schmidt orthogonalisation; binary PSK; blind equalisation; channel noise; constant modulus algorithm; different delays; fractionally-spaced constant modulus equalisers; improved convergence; length constraints; minimum mean square error; optimum delay; undesired local minima; zero constraints;

fLanguage

English

Journal_Title

Electronics Letters

Publisher

iet

ISSN

0013-5194

Type

jour

DOI

10.1049/el:19981157

Filename

715266