The service modeling and scheduling for wireless access network oriented Intelligent Transportation System (ITS)

This paper first describes the architecture and the main services of the wireless network oriented ITS (Intelligent Transportation System). The services of CVIS (Cooperative Vehicle-Infrastructure System) and PTT (Push To Talk) voice are analyzed and modelled. Pointed scheduling schemes are proposed for different services according to their QoS requirements. For CVIS service, vehicle speed adapted dynamic scheduling is adopted. For service of PTT voice, scheduling based on state transition is adopted. For video and other services which are not sensitive to delay, scheduling request is generated based on buffer status. Finally, the scheduling schemes are simulated on OPNET, from which the availability is verified with performance curve of delay and packet loss rate. And also, this provides reference for ITS access network design.