Non-linear multiuser detection for circuit-switched and packet-switched integrated CDMA systems

This paper assesses the impact of layered space-time multiuser detection (LAST-MUD) in wireless circuit switched and packet switched modes integrated CDMA systems. The network is hence composed of packet and circuit radio mobile stations transmitting to an antenna array at the base station receiver. These users are organized in different groups and users in a particular group are allocated the same spreading code. Therefore, the CDMA spreading technique will remove the interference between the groups and the layered space-time scheme will further remove the remaining interference between users. The effect of packet mode users on system performance is considered. Throughput and BER performances of packet and circuit mode users are hence investigated, respectively. The robustness of the LAST-MUD is also demonstrated against transmission power variation of packet mode users