Adaptive spreading code optimization in multiantenna multipath fading channels in CDMA

Author

Krishnamurthy, Vikram ; Wang, Xiaodong ; Yin, G.

Author_Institution

Dept. of Electr. Eng., British Columbia Univ., Vancouver, BC, Canada

Volume

4

fYear

2003

fDate

11-15 May 2003

Firstpage

2445

Abstract

The aim of this paper is to present discrete stochastic approximation algorithms for adaptively optimizing the spreading code of users in a CDMA system. The proposed algorithm can adapt to slowly time varying channel conditions. The most important property of the proposed algorithm is its self-learning capability - it spend most of the computational effort at the global minimizer of the objective function. A tracking analysis of the adaptive algorithms is also presented together with square convergence analysis. Numerical examples illustrate the performance of the algorithms in multipath fading channels.

Keywords

adaptive codes; antenna arrays; code division multiple access; fading channels; learning (artificial intelligence); least mean squares methods; multipath channels; optimisation; time-varying channels; CDMA system; adaptive algorithm; adaptive spreading code optimization; discrete stochastic approximation; mean square convergence analysis; multiantenna multipath fading channels; self-learning capability; time varying channel conditions; tracking analysis; Algorithm design and analysis; Approximation algorithms; Detectors; Fading; Filtering algorithms; Least squares approximation; Multiaccess communication; Signal processing algorithms; Stochastic processes; Transmitters;

fLanguage

English

Publisher

ieee

Conference_Titel

Communications, 2003. ICC '03. IEEE International Conference on

Print_ISBN

0-7803-7802-4

Type

conf

DOI

10.1109/ICC.2003.1204386

Filename

1204386