Decision aided MMSE-SIC multiuser detection for DS-CDMA systems

Abstract

This work presents a hybrid of the minimum mean square error (MMSE) multiuser detection (MUD) and successive interference cancellation (SIC) in conjunction with an information reuse scheme for direct-sequence code division multiple access (DS/CDMA) systems. The hybrid MUD first divides the users into groups with each group consisting of users with a close power level. The SIC is then used to distinguish users among different groups, while the MMSE MUD is used to detect signals within each group. T further improve the performance impaired by the propagation errors, a decision feedback scheme is added to attain more precise reconstructed outputs. Furthermore, a detailed performance analysis is conducted to provide further insights into the new approach. Furnished simulations show that the performance of the new MUD is very close to that of the MMSE MUD but with substantially lower computational complexity.