Time varying stochastic channel modeling of wireless DS-CDMA ad-hoc networks using different mobility models

The time varying nodes mobility and environmental changes in traditional ad-hoc channel creates limitation in signal propagation. In this study, a stochastic dynamic ad-hoc channel model is introduced with state space representation to overcome these limitations. The model´s parameters are computed from the approximation of Doppler spectrum. The performance of this stochastic ad-hoc direct sequence spread spectrum (DS-CDMA) wireless network in a flat fading channel is also investigated in this article. It is documented that the shape of the Doppler spectrum in a cellular network is considerably different than that of an ad-hoc network because of double mobility and speed. In this paper, the performance in terms of capacity and bit error rate (BER) under varying degrees of double mobility is demonstrated using simulation technique for stochastic ad-hoc model. As the degree of double mobility increases when the maximum Doppler shift is fixed, we observe that the capacity (number of users that can be supported) of DS-CDMA ad-hoc networks is higher than that of cellular networks because double mobility mitigates fading.