Allocation algorithm for optimizing MC-CDMA over correlated channel

In this paper, we address the problem of MAI (Multiple Access Interference) degrading the performance of a downlink MC-CDMA system in a frequency selective fading channel. Our objective is to develop a code allocation strategy subject to use any code family and any equalizer. This allocation problem is formulated as a minimization problem of a cost function related to MAI. Firstly, we build the cost function from an approximation of the analytical expressions of the MAI power for MRC, EGC and MMSE equalization. Then we propose an iterative algorithm based on the min-max criterion to select the spreading code of the active users. Simulation results show the efficiency of our allocation strategy versus key parameters, in particular the correlation degree between the faded subcarriers.