On the Performance of MC-CDMA Cellular Systems Employing Multiuser Decorrelating Detector and Antenna Array

The mean bit error rate (BER) for the uplink of a multicarrier-code-division multiple access (MC- CDMA) cellular system is evaluated. The system employs a multiuser decorrelating detector in the receiver, a uniform antenna array at base stations and perfect power control. The scenario assumes the presence of multiple access interference (MAI), co-channel interference (CCI), additive white Gaussian noise (AWGN), exponential path-loss and a slow frequency-selective Rayleigh fading. Expressions to evaluate the mean BER of the system are obtained, which are function of the signal-to- noise ratio (Eb/No), the channel reuse factor (F), the number of users (Nu), the spreading factor (G) and the number of antennas in the array (Y). Monte Carlo simulations are carried out to verify the tightness of the analytical expressions. The results show that the system diversity order is YG - Nu + 1. In some scenarios, when the number of antennas is increased, the system can be overloaded (Nu>G) and the mean BER maintains reasonable values.