In this paper a self-organized radio network for inter-vehicle communication (IVC) using broadcast messages is presented. The purpose of this network is to increase road traffic safety and to provide the driver with locally generated real-time traffic information. Therefore, each individual car transmits and receives broadcast packets that include floating car data (FCD) like position, velocity, road condition and visibility in a periodical way (e.g. every second). The periodical broadcast packets are also used to propagate summarized traffic information which has been received from other users in order to extend their accessibility far beyond the limited radio range of a single vehicle. Additionally, the transmission of delay-less data packets is foreseen in cases of emergency (e.g. crash, loss of traction), where an immediate and automatic reaction of the surrounding vehicles is required in order to prevent critical situations and further accidents. For collision-free access to the radio channel a reservation technique is considered which allows a self-organization inside the network. The system concept for a self-organized radio network and simulative results under realistic traffic situations are presented in this paper.
Abstract