Blind Multiuser Detection For Uplink CDMA Systems With Aperiodic Spreading Codes

This paper considers blind multiuser detection for uplink long code DS-CDMA systems. In this research, by taking the spread and scrambled chiprate signals as the inputs, the long code CDMA system is characterized with a time invariant multiple-input multiple-output (MIMO) model. Under this framework, multistep linear predictor-based (MSLP) method is applied to transform the system model from convolutive mixture mode to instantaneous mixture mode. As a result, classic independent component analysis methods can be used to recover the signals. Because the chip level signals are taken as the inputs, the proposed method supports multi-rate transmission inherently. Simulation examples are provided to illustrate the proposed approach.