Iterative Multiuser Detection with Soft Interference Cancellation for Multirate MC-CDMA Systems

Abstract

This paper presents an effective multi-rate multiuser detector (MUD) for the uplink of single-input multipleoutput (SIMO) multi-carrier code division multiple access (MC-CDMA) systems. The MUD considered is an iterative receiver which utilizes the soft information to refine the estimation of the interference to enhance the interference cancellation capability. More specifically, users with different transmission rates are classified into separate groups and, in each iteration, these groups of users are detected sequentially based on a set of minimum mean-squared error (MMSE) group detectors with the removal of multiple access interferences (MAI) group by group. Furthermore, the estimated interferences in each group, either from the same or the other groups, are refined successively with the assistance of the soft information in the symbol detection process. Conducted simulations show that the proposed MUD, with moderate computational overhead, can effectively suppress the MAI to render superior performance compared with previous works.

A novel code-based iterative PIC scheme for multirate CI/MC-CDMA communication

“…Multistage iterative interference cancellation has been found suitable in overloaded system [17][18][19]. Recently, iterative multiuser detection with soft IC for multirate MC-CDMA has been proposed in [20].…”

Convolutionally coded CI/MC-CDMA for wireless broadband communications

“…Significant performance improvement is obtained with iterative interference cancellation receiver for underloaded CDMA [3] and overloaded CDMA systems [4], [5]. Recently, iterative multiuser detection with soft IC for multirate MC-CDMA has been proposed in [6]. For multiuser environment, convolutionallly encoded multicarrier modulation is also examined in [7].…”