Performance evaluation of R-ALOHA for inter-vehicle communications at millimeter waves

The suitability of the R-ALOHA protocol for short range inter-vehicle communications in highway environments is investigated. In the context of road transport information (RTI) applications (such as, e.g., cooperative driving), in Europe the 63.5 GHz band has been recommended for inter-vehicle communications. Hence, network performance has to be evaluated by assuming a suitable propagation model; the joint impact of random access, interference, thermal noise, propagation and packet capture effect, is taken into account. The results obtained by means of a software tool that is able to simulate a one-lane highway scenario are presented. The simulation approach allows the evaluation of the impact of protocol parameters (such as, e.g., the number of slots per frame) on network performance. Only non-steady-state situations are analysed