Analysing Cooperative Awareness Message generation around intersections based on macroscopic traffic parameters

This paper describes the analysis of event triggered Vehicle-2-Vehicle messages around intersections. The study is based on naturalistic trajectory data recorded by drone on an unsignalized intersection. The microscopic traffic data available in the dataset is used to acquire macroscopic traffic parameters and to calculate Cooperative Awareness Message generations. The macroscopic traffic behaviour is compared with the CAM generation rates to analyse the relation between them, with the aim to support the estimation of the channel load due to vehicular communication based on macroscopic parameters in the future. The study demonstrates positive linear relationships between the CAM generation rate and the traffic density and between the generation rate and traffic flow. In addition, it was found that the trigger conditions based on change in heading and change in speed both have a significant effect on CAM generations for vehicles making a turn. Besides, it is concluded that the CAM generations of vehicles going straight ahead are mainly triggered due to the displacement condition.