V2V Channels and Performance of Multi-User Spread Spectrum Modulation

Vehicle to vehicle (V2V) communications have drawn much attention in recent years. In this paper, we discuss tradeoffs between implementation complexity and accuracy of several stochastic channel models for the V2V environment, and then address spread spectrum system performance attained using these channel models. Two different propagation environments are considered: urban and open areas (highways). The necessity of employing non-stationary channel models to accurately represent the channel is substantiated by comparing stationary and non-stationary empirical model outputs with measured data. A framework to compare single carrier direct sequence code division multiple access (SC-DS-CDMA) and multicarrier DS-CDMA (MC-DS-CDMA) performance in V2V channels is presented, and bit error ratio (BER) performance of the schemes is provided for the two channels. Our comparison of single- and multi-user performance shows that MC-DS-CDMA performs better than SC-DS-CDMA in both V2V environments.