Vehicles that can talk to each other, as well as roadside devices
Types of connectivity
Our team has been researching connected vehicles since 2013. A connected vehicle can ‘talk’ to other vehicles as well as roadside devices such as traffic signals. Currently connected vehicles can share information using two systems.
Cellular Vehicle to Everything (C-V2X)
Connected vehicles using C-V2X use mobile data networks to share information with other vehicles and infrastructure. About 300,000 vehicles in Australia today are already sharing information using C-V2X technology. Information shared includes traffic delays, rapid braking, slippery road conditions and distances between vehicles travelling in the same direction (known as headway distance). Vehicles using C-V2X technology can communicate with other vehicles and roadside infrastructure over vast distances, but need to be within range of a mobile phone tower. In areas without mobile phone reception, C-V2X will not operate.
Dedicated Short Range Communications (DSRC)
Connected vehicles using DSRC technology communicate with each other directly using a special radio frequency allocated by the Australian Communications and Media Authority for public safety information. In Australia, DSRC uses the 5.9 GHz band of the radio spectrum.
Vehicles using DSRC technology can ‘talk’ to each other over distances up to 1 km. DSRC technology can operate anywhere, even in areas where there is no mobile phone reception. Vehicles using DSRC have a device known as an on-board unit installed inside the vehicle. In 2020, Volkswagen became the first company in the world to release a mass-produced vehicle with a built-in DSRC unit.
How DSRC works
The DSRC device sends and receives information to and from other equipped vehicles and infrastructure 10 times a second. It uses that information to determine if a conflict is likely, based on comparing its own location, direction and speed to those of the other vehicles.
Drivers can be warned of risks on the road ahead, over the crests of hills or around bends. These systems may improve safety and reduce congestion.
Connected vehicle trials
The Centre for Road Safety has established Australia's first long-term connected vehicle testing facility, known as the Cooperative Intelligent Transport Initiative (CITI).