Wi-Fi location system is better than GPS, says start-up

A Boston, Massachusetts-based start-up says it has developed software that uses Wi-Fi signals to pinpoint locations better than satellite-based global positioning systems can.

On Monday Skyhook Wireless announced the commercial availability of its Wi-Fi Positioning System, or WPS. The software, which is now available to application developers and device manufacturers, uses 802.11 radio signals emitted from wireless routers to determine the precise location of any Wi-Fi enabled device, whether it be a PC, laptop, PDA, Tablet PC, smart phone or RFID tag.

The way it works is that the company has compiled a database of every wireless access point in a given a city. It did this by having people literally drive the streets "listening" for 802.11 signals. Using the unique identifier of the wireless router, it notes in the database where the access point is located.

When a mobile user running the Skyhook client pops up in a neighbourhood, the software scans for access points. It then calculates a user’s location by selecting several signals and comparing them to the reference database. The more densely populated the area is with Wi-Fi signals, the more accurate the software is at locating the device.

Ted Morgan, CEO of Skyhook said the location system is more accurate than global positioning systems that use satellites to find locations.

"GPS was designed by the military for guiding missiles," he said. "It performs poorly in urban areas where buildings block the view of satellites, and it doesn’t provide any coverage inside of buildings."

by Marguerite Reardon

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