Place Lab, a software that uses the signals from Wi-Fi base stations to calculate a user’s position is not as precise as GPS. It can provide accuracy to within 20 to 30 metres, whereas the GPS average is 8 to 10 metres.

But with improved algorithms that take into account, say, the height of the base station above the ground, or the building materials in the vicinity, it could get on a par with GPS in urban areas densely served with Wi-Fi.

Unlike GPS, Wi-Fi capability are increasingly installed for around an extra $30 on laptops, mobile phones and PDAs. And, once users have Wi-Fi, they don’t need to buy extra hardware to use Place Lab, and the software can be downloaded for free.

Researchers at the University of Glasgow (UK) are planning to test Place Lab’s positioning ability during 2004’s Edinburgh Festival in August – despite the city’s patchy Wi-Fi coverage. And in 2005, new software for the PDAs will help people find their way around Edinburgh and keep track of their friends.

The Place Lab team are working on other applications. A “location-aware” version of Microsoft’s Instant Messenger software is currently under development that will allow people to transmit their Place Lab data so that “buddy lists” will know when friends are online, but also where they are.

It could also be used to direct a user to the nearest petrol station or coffee bar, remind them their books are overdue as they pass the library, or warn them of traffic congestion ahead.

From New Scientist.
Related entry: Wi-Fi positioning system.