Delay Performance Of Vehicle Safety Applications In UMTS

Communication services inform the car and the driver about traffic and road conditions ahead before the car sensors have a chance to detect them and before the driver can see them. This paper considers the use of the already existing Universal Mobile Telecommunications System (UMTS) to support traffic safety and traffic management applications. for realizing delay critical hazard warning services. First, the authors provide an overview of the radio network capabilities for early UMTS standard releases as well as for recently added features such as the High Speed Packet Access (HSPA). Their analysis focuses on the delays experienced by both uplink message collection and downlink message distribution. Exemplary delay measurements in a live network are presented. They go on to analyze the potential of the Multimedia Broadcast Multicast Service (MBMS) with resource efficient point-to-multipoint transmission to large user groups. is analyzed. Finally, the relationship between delay performance and network resource consumption required for a hazard warning service is discussed and a concept proposal is given. This study is part of the activities of the Cooperative Cars (CoCar) project, which investigates car communication using cellular mobile communication technologies. The authors conclude UMTS dedicated and shared channels enable the shortest transmission delays but are optimized for point-to-point traffic consisting of large data portions. Common channels fit much better to the characteristics of the rare and small hazard warnings. The distribution of the same information to many users within a certain region can optimally be supported by using a constantly established broadcast bearer.