Efficient evaluation of the error probabilities of CDMA communication in mobile satellite channel

This paper is concerned with the analytical performance evaluation of direct sequence code division multiple access (DS-CDMA) signal transmission through a mobile satellite channel's system using Gold sequences. Because of the inaccuracy of the Gaussian approximation for the multiple access interference (MAI). An improved Gaussian process with good accuracy has been used. The impairments taken into consideration in the system are the non-linear effect of a travelling wave tube amplifier (TWTA) onboard the satellite (AM-to-AM and AM-to-PM conversions), additive white Gaussian noise (AWGN) and mobile propagation shadowing channel. The performance of the conventional detector receiver for MAI and the propagation channel modelled as shadowing (lognormal and Rayleigh) in suburban areas are evaluated both analytically and by importance sampling simulation. The obtained results of both the analytical and simulation methods, in terms of the dependence of the error probability on shadowing channel and the down-link noise at different values of input back-off of TWTA, are in good agreement.