I have a question concerning the implementation of the location API on cell phones. From what I've read so far, if there are no GPS satellites available, the implementation should switch to calculating the position with cellIds.
How is this done? Is just one basestation used or a couple of them to do some kind of triangulation? Does the basestation send coordinate information or does the implementation look up the coordinates in some table that converts cellIDs to coordinates? Does it need a GPRS connection to do this?
Where can I get more (detailed) information on this topic? I couldn't find much about this, I would really appreciate any pointers in this direction!