On the Connectivity of Vehicular Ad-Hoc Networks in Highway Scenarios

Modern vehicular technologies involve nowadays intelligent transport systems' (ITS) solutions, implying information technology, automation and communications. European Commission and transport organizations from worldwide are now focused on developing mobility as a service (MaaS), traffic safety, vehicular autonomy and environment protection. Vehicular ad-hoc networks (VANET), a specific subclass of mobile ad-hoc networks, has proven as an adequate support for a large number of safety-related mobile applications, such as: cooperative driving, cooperative collision warning/avoiding systems (CCWS/CCAS), environmental protection. However, some specific problems of these networks are caused by the large mobility of communicating nodes, which may lead to path interruptions or latency in transmitting emergency messages. This paper gives an evaluation of the connectivity on some case studies and presents possible solutions to cope with communication path disruptions on highways with low vehicle densities, addressing situations when not all vehicles are equipped with on-board units (OBUs).