Blind adaptive algorithms for minimum variance CDMA receivers

• Published in: IEEE transactions on communications Vol. 49; no. 1; pp. 180 - 194
• Main Authors: Zhengyuan Xu, Tsatsanis, M.K.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.01.2001; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Adaptive algorithm; Adaptive algorithms; Blinds; Constraint optimization; Constraints; Equations; Frequency; Interference constraints; Interference suppression; Least squares method; Mathematical analysis; Multiaccess communication; Multiuser detection; Optimization; Optimization methods; Receivers; Stochastic processes; Variance
• ISSN: 0090-6778; 1558-0857
• DOI: 10.1109/26.898261

Constrained optimization methods have received considerable attention as a means to derive blind multiuser receivers with low complexity. The receiver's output variance is minimized subject to appropriate constraints which depend on the multipath structure of the signal of interest. When multipath is present, the constraint equations can be written in parametric form, and the constraint parameters jointly optimized with the linear receiver's parameters. We develop adaptive solutions for this joint, constrained optimization problem. Both stochastic gradient and recursive least-square-type algorithms are developed. The performance of the proposed methods is compared with other blind and trained methods and turns out to be close to the trained minimum mean-square-error receiver.