Acquisition of multicarrier spread spectrum signals with correlated Rayleigh fading among its subcarriers

Multicarrier (MC) code division multiple access (CDMA) is an attractive way of implementing wideband CDMA systems while being backward-compatible with the existing narrowband CDMA systems. Initial acquisition in MC-CDMA has been studied for the case where the subcarriers experience independent fades. For many of scenarios, the assumption about the independence is unreasonable. We relax this assumption, and employ a realistic model for frequency correlation. We obtain an optimum receiver for initial acquisition that accounts for the frequency correlation, and present a technique for the analysis of this receiver. Finally, we study, by simulation, the tradeoff between the diversity gain available and noncoherent loss incurred as the number of subcarriers is increased.