Title :
Asymptotic analysis of widely linear MMSE multiuser detection-complex vs real modulation
Author :
Lampe, Alexander ; Breiling, Marco
Author_Institution :
LNT II, Erlangen-Nurnberg Univ., Erlangen, Germany
fDate :
6/23/1905 12:00:00 AM
Abstract :
We give the asymptotic signal-to-interference ratio for the so-called widely linear minimum mean-squared error multiuser receiver for transmission of multiple users to a common receiver with DS-CDMA. Observing that widely linear multiuser detection virtually doubles the spreading factor, we show that transmission with real-valued channel symbols can lead to a higher spectral efficiency than with complex-valued channel symbols when each user employs its own complex-valued random spreading sequence
Keywords :
code division multiple access; least mean squares methods; modulation; multiuser channels; radio receivers; radiofrequency interference; signal detection; spread spectrum communication; DS-CDMA; asymptotic analysis; asymptotic signal-to-interference ratio; complex modulation; complex-valued channel symbols; random spreading sequence; real modulation; real-valued channel symbols; spectral efficiency; spreading factor; widely linear MMSE multiuser receiver; Additive noise; Bandwidth; Closed-form solution; Covariance matrix; Gaussian channels; Interference suppression; Multiaccess communication; Multiuser detection; Nonlinear filters; Statistics;
Conference_Titel :
Information Theory Workshop, 2001. Proceedings. 2001 IEEE
Conference_Location :
Cairns, Qld.
Print_ISBN :
0-7803-7119-4
DOI :
10.1109/ITW.2001.955134
