Title
Convergence analysis of LMS multiuser CDMA detectors
Abstract
The convergence behaviour of the LMS CDMA multiuser detector is of great interest both in practice and in theory. The sampling rate for the tap-input of a LMS detector may be equal to or higher than the chip rate, and these correspond to chip-spaced (CS) and fractionally-spaced (FS) detection, respectively. It is shown in this paper that CS and FS detectors with the same time-span exhibit identical convergence behaviour, if the baseband received signal is strictly bandlimited to half the chip rate. Even in the practical case when this condition is not met, deviations from this observation are imperceptible unless the initial tap-weight vector gives an extremely large mean squared error (MSE). The inadequacy of the eigenvalue spread of the tap-input correlation matrix as an indicator of transient behaviour, and the influence of the initial tap weight vector on convergence speed, are highlighted. Specifically, initialization within the signal subspace or to the origin leads to very much faster convergence compared to initialization in the noise subspace
Year
DOI
Venue
1999
10.1109/WCNC.1999.797789
WCNC
Keywords
Field
DocType
bandlimited signals,signal sampling,sampling rate,chip rate,transient behaviour,tap-input correlation matrix,matrix algebra,baseband received signal,lms detector,mean squared error,convergence analysis,eigenvalue spread,chip-spaced detection,least mean squares methods,fractionally-spaced detection,convergence of numerical methods,receivers,code division multiple access,tap-input,signal subspace,lms multiuser cdma detectors,eigenvalues and eigenfunctions,signal detection,bandlimited signal,convergence,adaptive filters,wireless communication,least squares approximation,eigenvalues,chip,mean square error,correlation matrix,detectors,sampling methods,baseband
Convergence (routing),Baseband,Detection theory,Subspace topology,Control theory,Sampling (signal processing),Algorithm,Mean squared error,Real-time computing,Initialization,Signal subspace,Mathematics
Conference
ISSN
ISBN
Citations 
1525-3511
0-7803-5668-3
4
PageRank 
References 
Authors
0.70
3
3
Name
Order
Citations
PageRank
Teng Joon Lim12804169.48
Yu Gong241.72
Behrouz Farhang-Boroujeny397284.30