Triangulation algorithm using signal strength

Question

I want to have an estimation of the location of a user using the surrounding cell towers. For each tower, I have a location and a signal strength. Now I use a simple means of the coordinates but it is not very accurate (the user is not necessarily between the two towers).

I guess the solution is to draw a circle around each tower (the less the signal strength is, the larger it will be) and them compute the intersection between the circles. I usually don't have more than 3 cell towers.

Any idea how ? I found the Delaunay triangulation method but I don't think it applies here.

Thank you

Answer 1

You need to convert each signal strength to an estimate of distance and then use each distance (as the radius of a circle) in order to triangulate. You'll need at least three transmitters to resolve ambiguity, and accuracy will not be great, since signal strength is only very approximately related to distance and is affected by numerous external factors in the real world. Note that in ideal conditions, signal strength follows an inverse square law with distance.