Probabilistic tangent subspace method for multiuser detection

Abstract

The nonlinear Multiuser Detection (MUD) in Direct Sequence Code Division Multiple Access (DS/CDMA) system can be viewed as a two-class classification task. A new classification method called Probabilistic Tangent Subspace (PTS) is introduced to be used as an MUD. Due to the mobility of communicator, wireless communication channels are in fact time variant. The uncertainties of the time-varying channel's coefficients cause the uncertainties of the Multiuser Interference (MUI). On the other hand, the probabilistic tangent subspace method is designed to encode the pattern variations. Therefore, we are motivated to adopt this method to develop a classifier as a multiuser detector for time-varying channels. Simulation results show that this MUD performs better than that based on Support Vector Machine (SVM) for Rayleigh fading channel in DS/CDMA system. © Springer-Verlag Berlin Heidelberg 2005.