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No, it doesn't work that way -- it's actually rather ingenious. It turns out that a cell phone system can determine a phone's position with reasonable accuracy
by lutusp 13y ago
No, it doesn't work that way -- it's actually rather ingenious. It turns out that a cell phone system can determine a phone's position with reasonable accuracy by comparing its arrival times at different cell towers.
With two towers receiving a cell phone's signal, the phone can be located along a line. With three towers, it can be located as a point. It's all to do with the cell signal's arrival time, and it's sort of like radar in reverse.
No GPS needed. A GPS-equipped phone provides more accurate positions, but the passive cell-towers method is suitable for many applications.
http://farm4.static.flickr.com/3278/2867853394_7703d6c99f.jpg http://farm4.static.flickr.com/3278/2867853394_7703d6c99f.jp...
- MichaelGG 13y agoSure, and for 911 that's one thing. But the poster said GPS is saved in the CDRs, which is something I had not heard of. Otherwise it'd be best-of triangulation if needed. And I was under the impression that was only done for Phase 2 Wireless 911 calls. (And with far less accuracy than GPS.)