GPSOne is a technology that allows the handset and the network to cooperatively triangulate the location of the handset using both cell sites and GPS satellites. This information is computed on the network, based on handset and network supplied data, and fed to the 911 center during a 911 call. Not all networks support this functionality yet. And even better, the government demanding that carriers have this in place, don't have most of the 911 centers prepared to receive the data (ah, tax dollars at work....).
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