On Mon, May 3, 2010 at 8:18 PM, Risto H. Kurppa <ri...@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. _______________________________________________ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community