A linear programming algorithm for a grouped MC-CDMA system

In this paper we present an adaptive linear programming based algorithm to exploit the multi-user diversity present when communicating to multiple users on a multicarrier CDMA (MC-CDMA) downlink. Utilising the received channel characteristics as the adaptation criteria, we adaptively allocate subcarriers to groups and thereafter adaptively assign users to those groups (the grouping is done to allow the use of a maximum likelihood multi-user detector (ML-MUD)). The objective in performing this adaptive grouping and allocation is to improve the quality of service (QoS) - in terms of bit error rate (BER) - seen by users in the system. Employing a simulation study, we compare the results of the proposed linear programming algorithm with the results of other approaches from the literature. These results show that the proposed algorithm gives better QoS performance, for more users in the system, than previous approaches.