Tools to determine exact location when using ibeacons

Question

We are working with a Retail client who would like to know if using multiple iBeacons throughout the store would help track a customer\'s exact location when they are inside the

Answer 1

The solution is a technique called trilateration. There is a decent wiki article on it.

If you assume that all the beacons and the receiver are on the same plane you can ignore the Z dimension and it simplifies to circles.

The math is still kind of messy. You'd have to do some matrix math on the positions of the beacons to shift one beacon to the origin and put a second beacon on the x axis, and then apply the inverse of your matrix to the result to convert it back to "real" coordinates.

The big problem is that the "accuracy" (aka distance) value is anything but accurate. Even in a wide open space with no interference, the distance signals vary quite a bit. Add any interference (like from your body holding the phone even) and it gets worse. Add walls, furniture, metal surfaces, other people, etc, and it gets really wonky.

I have it on my list of things to do to write trilateration code, measure out a grid in my yard (when the weather warms up), take a tape measure, and do some testing.