Can the location of a WiFi access point be triangulated with the following data?

Question

Let's say I have 3 or more peers connected to the same WiFi Access Point.

If they all give me: - latitude - longitude - their signal level (dBm) in respect to the same WiFi

Is this enough data to get the approximate location of the access point?

Answer 1

Yes, sort of. You would need a way to convert signal level to a distance from the access point. You may need to know the power of the signal (watts, mW, etc) in order to do this conversion. There's some interesting reading from Cisco here, but being indoors can cause large errors because physical objects (like walls) in between the two antennae will cause further power loss in the signal.

There are a couple of calculators that might be useful at Radiolabs.

Answer 2

Not in all possible situations. Each user will provide you with a circle of potential access point locations. The radius of the circles will be dependent on signal strength at the given location.

It is entirely possibly to draw three (or more) circles that all intersect at more than one point. The simplest example would be if all users were at the exact same location, but it is very easy to draw three circles of variable radius that intersect at two or more locations.