Iterative Turbo MMSE Successive Parallel Arbitrated Decision Feedback Detectors for DS-CDMA Systems
Rodrigo C. de Lamare, Raimundo Sampaio‐Neto · 2008
In this paper we propose iterative turbo minimum mean squared error (MMSE) successive parallel arbitrated decision feedback (DF) receivers for direct sequence code division multiple access (DS-CDMA) systems. We describe the MMSE design criterion for DF multiuser detectors along with successive, parallel and iterative interference cancellation structures. A novel efficient turbo DF structure that employs soft-decision successive cancellation with parallel arbitrated branches and a near-optimal low complexity user ordering algorithm are presented. The proposed iterative turbo DF receiver structure and the ordering algorithm are then combined with iterative cascaded DF stages for mitigating the deleterious effects of error propagation for uncoded systems. Simulations for an uplink scenario show substantial gains for the proposed iterative turbo DF detectors over the best known methods.