locating via GSM, revisited

[Harald Welte]

On Mon, Apr 21, 2008 at 05:59:29PM +0800, joerg at openmoko.org wrote:
> Am Mo  21. April 2008 schrieb Werner Almesberger:
> > joerg at openmoko.org wrote:
> > > For many countries there are ageold databases created by hobbyists doing 
> > > antenna-spotting. In Germany, carrier O2 sends quite exact Gauss-Krueger 
> > > coordinates on CBC 221 for each of his stations.
> > 
> > Okay, that's good. So we can have a comprehensive geographical database
> > we can put our "GSM n-space" in relation to. (Although no motivation
> > was ever stated, I'm assuming here that the goal of the whole exercise
> > is to avoid using GPS. Thus we can't correlate vectors we measure in
> > GSM n-space to 2D or 3D real-world vectors we measure with GPS.)
> > 
> > Is there something like openstreetmap with these antenna locations or
> > does one have to hunt and gather from scattered repositories ?
> 
> Dunno...

At least in Germany the location of the cellular towers (especially
combined with the information if they're GPRS, EDGE, UMTS or HSDPA) is
considered a trade secret by the operator.

If you create free databases with that kind of stuff, be sure you have
sufficient stack to fight the legal battles.

Cheers,
-- 
- Harald Welte <laforge at openmoko.org>          	        http://openmoko.org/
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