Title
Blind Adaptive Constrained Constant-Modulus Reduced-Rank Interference Suppression Algorithms Based on Interpolation and Switched Decimation
Abstract
This work proposes a blind adaptive reduced-rank scheme and constrained constant-modulus (CCM) adaptive algorithms for interference suppression in wireless communications systems. The proposed scheme and algorithms are based on a two-stage processing framework that consists of a transformation matrix that performs dimensionality reduction followed by a reduced-rank estimator. The complex structure of the transformation matrix of existing methods motivates the development of a blind adaptive reduced-rank constrained (BARC) scheme along with a low-complexity reduced-rank decomposition. The proposed BARC scheme and a reduced-rank decomposition based on the concept of joint interpolation, switched decimation and reduced-rank estimation subject to a set of constraints are then detailed. The proposed set of constraints ensures that the multipath components of the channel are combined prior to dimensionality reduction. We develop low-complexity joint interpolation and decimation techniques, stochastic gradient, and recursive least squares reduced-rank estimation algorithms. A model-order selection algorithm for adjusting the length of the estimators is devised along with techniques for determining the required number of switching branches to attain a predefined performance. An analysis of the convergence properties and issues of the proposed optimization and algorithms is carried out, and the key features of the optimization problem are discussed. We consider the application of the proposed algorithms to interference suppression in DS-CDMA systems. The results show that the proposed algorithms outperform the best known reduced-rank schemes, while requiring lower complexity.
Year
DOI
Venue
2011
10.1109/TSP.2010.2091274
IEEE Transactions on Signal Processing
Keywords
Field
DocType
reduced-rank interference suppression,interference suppression,low-complexity reduced-rank decomposition,blind adaptive constrained constant-modulus,reduced-rank scheme,proposed algorithm,reduced-rank decomposition,blind adaptive reduced-rank,reduced-rank estimator,reduced-rank estimation subject,transformation matrix,switched decimation,blind adaptive reduced-rank scheme,algorithm design and analysis,optimization,switches,complex structure,interpolation,iterative methods,wireless communication,spread spectrum,wireless communications,algorithm design,code division multiple access,optimization problem,estimation,iteration method
Signal processing,Mathematical optimization,Decimation,Dimensionality reduction,Selection algorithm,Interpolation,Algorithm,Adaptive algorithm,Optimization problem,Recursive least squares filter,Mathematics
Journal
Volume
Issue
ISSN
59
2
1053-587X
Citations 
PageRank 
References 
42
1.16
26
Authors
3
Name
Order
Citations
PageRank
de Lamare, R.C.165233.42
R. Sampaio-Neto21388.48
M. Haardt349545.19