Space-Time Adaptive MMSE Multiuser Decision Feedback Detectors with Multiple Feedback Interference Cancellation for CDMA Systems

In this work, we propose a novel adaptive space- time MMSE decision feedback detection scheme, which employs a structure with multiple-parallel feedback branches (MPF) for interference cancellation and combines this novel structure with antenna arrays using both diversity and beamforming configurations. Our proposed adaptive DF algorithm can be used in several scenarios, including MIMO and MC-CDMA systems. In this paper, we focus on the application to DS-CDMA systems and the use of adaptive algorithms for parameter estimation. Simulation results for an uplink scenario with uncoded systems assess the proposed MPF-DF detector against the best known schemes and show that it achieves a substantial capacity increase over existing schemes.