Highway Wi-Fi: How the new tracking system works

A Europe-wide car tracking system may sound far-fetched, but the scientists behind the scheme say the technology required to make it happen is already part of our everyday lives.

The system uses the same connections as those in mobile telephones, Wi-Fi internet and security tags attached to clothes in shops.

A car will constantly stay in touch via all these methods of communication, stashed in a router behind the dashboard.

Crucially, vehicles beam out a "heartbeat" message, revealing their precise location, speed and direction, to all other cars within a 400m range.

The heartbeat can send out other messages which, scientists say, will save lives. So when a car is forced to brake hard, or its wheels encounter a slippery surface, that information can be supplied to other drivers in the area.

Vehicles can also communicate with the "roadside infrastructure", with beacons implanted in gantries or bridges to give and receive information. So traffic lights or intersections will be alerted when vehicles are approaching, while in return cars will be told about congestion ahead.

Scientists believe the data will be of most use for traffic controllers, who - without the use of cameras - will be able to know exactly where vehicles are on the roads and respond appropriately.