all you really need to do to triangulate is measure the signal strength from at least 3 towers, which should give you plenty of data to pinpoint the precise location of the broadcast. you could do it with 2 directional antennae too, where you could get range and direction, and if you knew the tx power of the transmitter in the phone, you could probably find it with one directional antenna or two towers. what is scary is that the company would keep logs of the returned signal strength of your calls, but im sure there are reasons for this, such as to generate statistics on usage for network maintenance and upgrades, or to keep track of your location so they can match you up to the closest tower for best communication.