Posted by Resident, a resident of Another Palo Alto neighborhood, on Jun 10, 2008 at 9:15 am

Am I asking a dumb question? If these units can find satellites, why can't satellites find them as soon as they are switched on? If every unit was able to broadcast an identifying marker so that stolen units could be identified, then they would be useless on the stolen market front?

Posted by Sunay, a resident of the Midtown neighborhood, on Jun 10, 2008 at 5:02 pm

I think the protocol is one way i.e. satellites transmit the signals and the GPS unit uses 3 or more satellite to triangulate its own position. I

don't think the GPS unit can talk to the satellite.