Code acquisition in CDMA cellular mobile networks. Part I: Theory

The problem of acquiring code synchronization in a CDMA cellular mobile network is addressed in this paper. The fundamental issue is to set a theoretical framework for the analysis of the acquisition subsystem that remains valid in the presence of fading and shadowing effects with specified coherence time. A multi-dwell architecture adopting the MAX/TC criterion is considered, and the acquisition performance is analyzed using both the direct approach and the flow-graph approach. Expressions for the acquisition time probability density function under different assumptions are given. The conditions under which the Markovian nature of the acquisition procedure can be assumed to be preserved in a fading channel are discussed. Closed form expressions for the mean and variance of the acquisition time are reported.