April/May 2002

A method of gathering real-time traffic information that promises more accurate journey time predictions than any previously available is being tried on the European mainland.

Communications group CMG is behind the pilot scheme, which uses call data from mobile telephones to analyse traffic flows and predict journey times. It is working with a so-far un-named European mobile telecoms company.

Having gathered data on the location of each mobile (derived from knowing which "cell" it is using), it processes this to calculate the driver's approximate speed between cells, then relays the information directly back to the mobiles (or linked PDAs). The hundreds of thousands of people making mobile telephone calls on the move therefore represent both a vast real-time database, and potential service users.

 

CMG believes that reliable journey time predictions are crucial for bringing wide acceptability to traffic information systems. According to Alistair Cole, associate director of CMG's transport, logistics and commerce division: "It's not enough to tell drivers they're in a two-mile traffic queue. They also need to know how long it will take them to get through it."

Wireless network providers such as mobile phone companies do not of course routinely transmit cell details to the user's phone, but do monitor the information for their own use. Each time a mobile phone is used on the network, the operators records real-time data about the call, including time and cell location. If the caller is moving, the call transfers seamlessly from one cell to the next.

The network service providers use the data for billing, but CMG is using it to produce real-time information about traffic flows, based on the time taken for the call to shift from one cell to the next.

It's not that simple, of course. The CMG software has to translate the cell-based locations into road network information, and the data must be cleaned using hard-coded algorithms that sift out irrelevant calls and meaningless data.

In the trial, the CMG software polls the call data records every 15 minutes, although more frequent polling is possible. There are no data protection issues, says Cole, because individual callers are not identified.

Cole says how the CMG technology is developed lies in the hands of the telecoms companies. "Some take a holistic view of their network and are very receptive to new applications and services, other are interested only in selling airtime, and in network development." Telecoms companies can charge for access to the records, leaving it to the application provider to take it to market. Alternatively the telecoms provider can be both the supplier of the cell data and the channel to market, or it can operate a joint-venture.