Title :
A novel iterative multiuser detector for complex modulation schemes
Author :
Lampe, Alexander ; Schober, Robert ; Gerstacker, Wolfgang ; Huber, Johannes
Author_Institution :
Lehrstuhl fur Informationsubertragung, Erlangen-Nurnberg Univ., Erlangen, Germany
fDate :
2/1/2002 12:00:00 AM
Abstract :
A novel multiuser detector for direct sequence code division multiple access is proposed. The receiver performs iterated soft decision interference cancellation (ISDIC) based on multiuser interference suppression filters designed for minimization of the mean-square error. Assuming a complex modulation format, we show that the multiuser interference becomes rotationally variant in the course of the iterations. Regarding this rotational variance in the design of the multiuser interference suppression filter, the presented iterative multiuser detector achieves significant performance gains compared with conventional ISDIC employing a standard minimum mean-squared error filter which is optimum only for rotationally invariant multiuser interference
Keywords :
code division multiple access; filtering theory; interference suppression; iterative methods; least mean squares methods; modulation; multiuser channels; radio receivers; radiofrequency interference; signal detection; spread spectrum communication; MSE minimization; complex modulation schemes; direct sequence code division multiple access; iterated soft decision interference cancellation; iterative multiuser detector; mean-square error minimization; minimum mean-squared error filter; multiuser interference suppression filters; receiver; rotationally invariant multiuser interference; Additive noise; Covariance matrix; Detectors; Direct-sequence code-division multiple access; Interference cancellation; Interference suppression; Matched filters; Modulation coding; Multiaccess communication; Nonlinear filters;
Journal_Title :
Selected Areas in Communications, IEEE Journal on
