THE last call the victim made on her mobile phone was to the emergency services. It lasted for 2 minutes and contained a sequence of muffled sounds, but the police were unable to respond because they had no idea where she was when she made the call. The next day her body was found in undergrowth, and six months later the murder is still unsolved.
If there is anything positive to be taken from cases like this, it is that they are a force for change. In September, a European Union directive called E112 came into force that requires mobile phone networks to provide emergency services with whatever location information they have about where a mobile phone call was made. Such a system might not have saved a life in this case, but it may well save others.
When a similar scheme was introduced in Britain for landlines a few years ago, response times to emergency calls improved dramatically, says Quentin Armitage, deputy director of technology for the London Ambulance Service. The aim is to make a similar improvement for cellphone emergency calls.
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While Europe is leading the way on cellphone positioning, other countries are not far behind. In the US a similar law will force network operators to track a phone’s location to within 50 metres by 2005, and to make this data available to emergency services.
Network operators have been quick to spot the business opportunities this offers. If they can locate a caller for the emergency services, why not for other purposes too? Now the first businesses to exploit this information are beginning to appear and they provide a glimpse of the kinds of services we can expect in future.
In the UK, the network operator Vodafone leads the pack. As the only one of the nation’s five major mobile network operators to have met the EU directive’s September deadline, its customers can already use their phones to find the nearest ATM, cinema or a plumber through WAP (wireless application protocol), the stripped-down web service designed for mobile phones. Just tell your phone that you want a flower shop or a Chinese restaurant and it searches local telephone directories to find the nearest hit.
Another service allows businesses to track their employees – particularly useful in the courier industry, for example. And a London-based start-up called Zingo has begun exploiting the service to put callers in touch with the nearest available taxi. Parents can even sign up to see where their children are, or at least where they left their mobile phones.
Similar services are becoming available in other countries. A Stockholm-based company called It’s Alive has launched a game that lets people hunt each other using their phones. And in the US, the Houston-based start-up Findtheone.com plans to offer phone owners a dating service that will alert them when potential partners who have also signed up are nearby. This is just the beginning. Expect to see services become more accurate and widespread as the technology develops.
Of course, there are teething problems. You could be forgiven for being underwhelmed with the positioning accuracy. Call Zingo, for example, and you may end up having to tell a human operator where you are if the system can’t get a fix on your phone.
And what of fears about sinister surveillance? There is always going to be something slightly Orwellian about being automatically tracked. But the companies involved insist that personal privacy will not be compromised. “You don’t have to register to use our service,” says Ian Read of Zingo. “We are not worried about privacy issues because we don’t know who you are.”
How the Networks Locate a Phone
Pinpointing mobile phones within a network is relatively straightforward. The networks are divided into cells which range in size from 2 kilometres across to only 500 metres across in dense city centres. The coarsest form of positioning simply identifies the cell from which a call was made, but more accurate methods are in the pipeline.
One of the most promising relies on the European networks’ ability to measure how long signals take to travel from a phone to a base station, thereby giving its distance. That pins down the phone to a narrow circular band around the base station. The next step is to use readings from two other base stations to triangulate the phone’s position.
The networks will need to be modified to do this automatically, says Anne Jones, who manages the location-based services at Vodafone in the UK, but the upgrades are already planned. When they come into action in the next few years, the positioning data should be accurate to within 50 metres.
Another option is to build satellite-based GPS location systems into phones. These can fix the receiver’s position to within a few tens of metres, anywhere on the planet. And by factoring in position data from base stations an accuracy of 5 metres will be possible.
