A Novel Signal Enhancement Scheme for Adaptive Antenna Arrays in Multirate DS/CDMA Systems

Kyungseok KIM  

Publication
IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences   Vol.E87-A   No.10   pp.2780-2789
Publication Date: 2004/10/01
Online ISSN: 
DOI: 
Print ISSN: 0916-8508
Type of Manuscript: PAPER
Category: Spread Spectrum Technologies and Applications
Keyword: 
adaptive antenna array,  DS/CDMA,  array signal processing,  

Full Text: PDF>>
Buy this Article




Summary: 
A novel signal enhancement scheme using the rotation of signal subspace (RSS) and Toeplitz matrix approximation (TMA) methods to enhance the performance of an adaptive antenna array in multirate DS/CDMA systems is proposed. The basis of RSS is to find a transformation matrix in order to recover the desired complex array covariance matrix from a sampled complex array covariance matrix which is contaminated by an interference-plus-noise component, which is the total noise. Also, the objective of TMA is to change the output matrix of RSS into a matrix having the theoretical properties of a total noise-free signal. Consequently, the proposed signal enhancement scheme using RSS and TMA methods can greatly improve the performance of an adaptive antenna array by reducing the undesired total noise effect from the sampled complex array covariance matrix of the pre-correlation received signal vector that is used to calculate a weight vector of an adaptive antenna array. It is shown through various simulation results that the system performance using the proposed signal enhancement scheme is much superior to that of the conventional method.