By M. Moinuddin, A. U. H. Sheikh, A. Zerguine
In this work, analysis of the multiple access interference (MAI) for synchronous CDMA systems is carried out for the BPSK modulation with random signature sequences in additive white Gaussian noise (AWGN) environment. In this analysis, downlink scenario is considered for two different cases: (1) with perfect power control, and (2) with imperfect power control. Expressions for the probability density function (pdf) of MAI and MAI plus noise are derived for the two cases as a function of number of users and spreading factor. Gaussian approximation is also developed for these scenarios. Close agreement between analytical analysis and simulation results is obtained for different scenarios of number of users and spreading lengths.