Multistage Interference Cancellation for Multirate DS/CDMA on a Mobile Radio Channel

A novel hybrid interference cancellation (IC) scheme is proposed for the uplink of multirate directsequence code division multiple access (DS/CDMA) systems communicating over mobile radio channels. The hybrid IC scheme includes both non-decision directed and decision directed IC, joined together with a modified RAKE combiner for utilization of the diversity. The performance is evaluated via computer simulations for two multiple data rate schemes, mixed modulation and parallel channels, in a multipath environment. Both the case of known channel parameters and channel estimation using pilot symbols are considered. An analytical performance assessment is also given using a Gaussian approximation.