DEVELOPMENT, IMPLEMENTATION AND EVALUATION OF AN ARCHITECTURE FOR VEHICLE-TO-VEHICLE AND VEHICLE-TO- INFRASTRUCTURE NETWORKING

In this doctoral thesis the development, implementation and evaluation of the architecture for a vehicle-to-vehicle and vehicle-to-infrastructure access network have been presented. The work started in 2006, when the original concept of the intelligent hybrid wireless traffic service architecture between cars supported with wireless transceivers on the roadside was initially presented. The original communication architecture was based on traditional Wi-Fi communication between vehicles and infrastructure, supplemented with GPRS (General Packet Radio Service) communication within a cellular GSM network as the backbone access method. The original wireless traffic service architecture developed in this work presented an innovative solution for hybrid vehicular networking, based on wireless networking and mobile communication solutions available at that time. The enhanced access network protocol standard and mobile access system with commercial equipment available allowed the further development of the architecture. The key objective was to provide an intelligent hybrid wireless traffic safety network between cars and infrastructure, relying now on a short-range (local wireless vehicular) access network, combined with the overlay cellular network. Furthermore, there was a set of example services concentrating on accident warnings (both critical and minor incidents) and road weather data, reflecting rather well the general type of vehicular networking services, and employing the platform resources, both in terms of capacity and reaction time. The IEEE 802.11p vehicular communication standard based platform was first tested in an extensive set of different kinds of vehicular networking scenarios. The communication capacity and connectivity was tested in vehicle-to-infrastructure, vehicle-to-vehicle, as well as vehicle-to-vehicle-to-vehicle communication entities. The field tests with a limited amount of vehicles were extended into simulation scenarios with a larger platoon of vehicles. The resulting communication platform was found to be appropriate for the preliminary example services, and finally the entire architecture, together with 3G backbone communication and embedded services, was pilot tested in the demonstration system. This communications architecture, particularly tailored for vehicular networking, is the main topic of this thesis. The further development of the communication architecture focuses more and more on near-the-market services and multi-standard communication. Both of these goals are combined in the Finnish Meteorological Institute approach to employing a vehicular networking entity to provide route weather information for vehicles passing our combined Road Weather Station (RWS)/Road Side Unit (RSU). Route weather is a special type of weather service tailored for dedicated road stretches, based on a road weather model and data collected from local RWSs and from vehicles themselves.