Status of GSM base station positioning services & clients

Alex (Maxious) Sadleir maxious at gmail.com
Mon May 3 13:28:12 CEST 2010


On Mon, May 3, 2010 at 8:18 PM, Risto H. Kurppa <risto at kurppa.fi> wrote:
> Hi there!
>
> does anyone know what's the current status of GSM base station -based
> positioning services..
> How do the different databases compare to each other nowadays?
>
> Are there clients to position the user based on the GSM base stations,
> with on- or offline databases?
> It'd be great to be able to detect the approximate location from GSM
> signal and then hook up to GPS faster..

You can get the approximate locations of the celltowers detected
nearby with both the cellhunter and openbmap APIs (online). Averaging
these and scaling by signal strength gets an alright accuracy
(100-500m in some places). AFAIK there isn't an openmoko client for
doing that.

This accuracy would be better with WLAN essid locations like
Google/Skyhook do... I notice openBmap now has "wifi data" being
uploaded on their website so you might be asking at just the right
time. There is a specification for wifi uploads (
http://sourceforge.net/apps/mediawiki/myposition/index.php?title=Wifi_log_format
) that is used on Windows Mobile but the openmoko client hasn't been
updated to publish this as far as I know. I would certainly be very
excited to collect more data if it was updated :)

There is a project called openbmap-locator that uses an offline
version of the openbmap database to emulate a GPS interface via
fso-ogpsd ( http://github.com/baruch/openbmap-locator ). It has a few
compile time dependencies on SHR including vala which I had to
download a tarball for and compile instead of using opkg (i'm sure if
you have a desktop OE buildenv, it's much easier). The first time you
run it, it downloads a testing sqlite database to
~/.openBmap/cellid.db
It is supposed to be possible to download an updated SQL database
using a URL like
http://openbmap.org/latest/cellular/244_sqlite_zones.zip where 244 is
the MCC for the country you want... but there isn't a file for finland
and the file for australia (505) seems corrupted. Germany (262) works
fine but that's not where I am and I don't know how to convert/import
it to sqlite. So all in all, needs some more help to get it ready for
normal users.



More information about the community mailing list