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Trilateration

Posted: Mon Jun 27, 2016 8:45 am
by csteddy
Hi,
I'm wondering why the accuracy of the location of the source of each SSID (usually a router) doesn't increase over time with greater sampling? I would have thought that my own SSID would be pinpointed to my house, rather than 30 or 40m away?

Regards,

Craig

Re: Trilateration

Posted: Sun Jul 03, 2016 2:58 pm
by bobzilla
It should, if there are observations from all sides. If all observations are on the north side of a device, it will always appear to be north of its actual location.

Re: Trilateration

Posted: Tue Jul 26, 2016 8:46 am
by csteddy
The Android app itself seems to be quite accurate, but not the website map. I'll do some investigation and give a few examples.
btw. How to you deal with outlier samples (eg. a router is moved, or a wacky GPS co-ord)?

Re: Trilateration

Posted: Sat Jul 30, 2016 8:23 pm
by bobzilla
There's an iterative filtering that biases towards newer clusters.