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Wi-Fi location accuracy

Posted: Thu Apr 11, 2013 10:33 pm
by comesunt

I am very keen to determine the location accuracy of wireless APs shown on Wigle.

I looked at the interactive map and found an AP with an address as the SSID, ( 52HolmeLacyRoad ) so sought to see how accurate the plotted location was.

I then put the BSSID ( 00:26:F2:bf:09:22 ) in the field
Query for location data of a single network, where a table was produced showing all the fixes for that BSSID.

My questions are as follows:

In the table that is displayed, in the field "accuracy" where is this value coming from? Is it a translation of the HDOP?, and if so, can anyone offer what the algorithm is?
Additionally, can anyone advise where the value in the field "weight" is obtained from?
Further more, can anyone offer any suggestions on how the location placed on the map is determined ?

Many thanks,


Re: Wi-Fi location accuracy

Posted: Fri Apr 12, 2013 12:08 am
by uhtu
from the FAQ:

The "triangulation" is actually just an average of the latitudes and longitudes gathered using the signal strength (squared) as a weight. This assumes that signal strength will change at the inverse square of the distance. This is reasonable as long is you don't get a one sided view of the network (IE only sample it on the west side) since it will be skewed in that direction. Perhaps a better way would be choosing a signal of 70 as being the ultimate, and every other point being a radius from 70 and trying to find where all the circles intersect, but we'll see. This should be good enough for the real world for now.

accuracy is in horizontal meters, which comes from the various nefarious stumble software packages. weight is the signal strength, also from said softwares.