For some time now, the protagonists of vehicle networking have been working on implementing future V2X services based on 5G mobile technology. The advantage of 5G over the DSRC technology with the IEEE802.3p radio standard, which was originally designed for this application, is that 5G offers the possibility of integrating services in the cloud or in the OEMs’ backend computers via a connection to the mobile network. And all this without having to accept significant reductions in the reaction speed of the systems, as was the case with previous generations of mobile communications. This technology thus extends the range far beyond the visual range – one of the major limitations of the older DSRC technology.
As part of the project, the participants, under the leadership of the automotive supplier Bosch, developed essential technical and operational principles for the series-production readiness of this technology in the areas of networks, security, and communication protocols. The project thus cleared obstacles on the way to standardization of this technology and opens up the possibility of series production and the development of new business models. Among the participants were the car manufacturers BMW and Volkswagen, telcos Deutsche Telekom and Vodafone, equipment suppliers Ericsson and Nokia as well as the Technical Universities of Dresden and Kaiserslautern and the Fraunhofer Heinrich Hertz Institute.
By means of the technology developed, vehicles can exchange data with each other in real time (V2V). At the same time, the technology offers the possibility of implementing communication applications between vehicles and infrastructure (V2I) and between vehicles and the network (V2N). On this basis, the partners in the 5G NetMobil project developed, for example, an intersection assistant that protects pedestrians and cyclists at unclear intersections. A camera installed in the infrastructure detects pedestrians and warns vehicles within a few milliseconds to prevent critical situations, e.g. when turning off. Another example of the research project is platooning: This allows commercial vehicles to join together in so-called platoons and drive at very close distances to each other. Acceleration, braking and steering interventions are synchronized by V2V communication. Automated slipstream driving in convoys significantly reduces fuel consumption and increases safety on the motorways. Platooning applications can also be found in agriculture – although the vehicles drive parallel across the fields.
One challenge for this form of real-time communication was the uneven quality of the wireless data connections: If the connection is poor, the data rate drops dramatically and the error rate of the transmission increases. The project participants developed an agile quality-of-service concept that detects changes in network quality and passes them on to the networked driving functions. During platooning, the distances between the individual vehicles in the convoy can thus be automatically increased if the quality of the network deteriorates.
Another research focus was the division of the mobile radio network into individual virtual networks within the main network (slicing). A separate subnetwork is now used for data transmission for safety-critical functions such as warning pedestrians at an intersection to ensure the reliability of this function at all times. Data transmission for video streaming or updating the road map is controlled in a separate virtual network and is temporarily postponed if only a low data rate is available. Furthermore, the research project has made significant contributions to the hybrid communication of mobile radio and the WLAN-based alternative, in which the most stable connection is used in each case so that the data connection does not break down while on the move.
The knowledge gained in the project is now to be incorporated into the worldwide standardization of the communications infrastructure and serve as an essential basis for further developments by the partner companies.