Performance Enhancement of MC-CDMA Systems through MAP based Multiuser Detection

The joint Multiuser Detection (MUD) and turbo coding are the two powerful techniques for enhancing the performance of the MC-CDMA systems. The Multiple Access Interference (MAI) is one of the factors that affect the Bit Error Rate (BER) performance of the MC-CDMA systems. Maximum a posteriori (MAP) criterion based multi user detector greatly improves the system performance and mitigates the effects of MAI. However its complexity increases exponentially with increase in number of users. In this paper a Logarithmic-MAP (LOGMAP) based MUD is proposed for the MC-CDMA systems. It is shown that the proposed LOG-MAP based MUD scheme improves the BER of the system greatly and it also reduces the MAI and complexity of the system.