updated 12:05 pm EDT, Tue September 30, 2008
Broadcom GPS with Wi-Fi
Broadcom on Tuesday said it would start integrating Wi-Fi support into its GPS navigation chips, letting cellphones and other devices equipped with the hardware use the local network for positioning. The technique draws on a license from Skyhook that uses known Wi-Fi points to triangulate a rough map location when GPS is unreliable or completely unavailable and should both generate a GPS lock faster in urban areas as well as fill in when indoors or in tunnels where the GPS signal is blocked.
The development potentially expands the use of short-range networking for positioning in cellphones equipped with both GPS and Wi-Fi in the same device, which in many cases have been limited to using either technology separately. Most phones with assisted GPS, such as Nokia's Nseries devices, rely primarily on Internet data from central servers to speed up acquisition rather than reaching out to nearby connections.
Apple's iPhone 3G is one of the few phones so far to currently take advantage of such features, regardless of platform, and uses Skyhook's Wi-Fi triangulation to provide a rough fix before using true GPS on a Broadcom-based Infineon chip as well as cellular tower triangulation to generate a more precise location.