Asymptotic spectral efficiency regions of two-user MC-CDMA systems in frequency-selective Rayleigh fading

In this paper we derive asymptotic performance measures for multiuser receivers in the uplink of multi-carrier (MC) CDMA communication systems with multiple signatures per user. We examine spectral efficiency regions of multi-signature CDMA, for both the optimal and optimal-linear receivers. We also derive an approximate expression for the asymptotic average signal to interference and noise ratio at the output of the optimal-linear multiuser receiver in the case of two users. Simulation studies demonstrate that the asymptotic results closely predict performance of practical finite systems.