Is wifi/bluetooth Triangulation(not trilateration) using a mobile device possible?

Question

Well for triangulation you need to have the direction from which your device is receiving the signal.We can calculate Angle of Arrival for

Answer 1

Mobile mast triangulation usually uses the power level to estimate how far a phone is from a particular cell tower. At any given time a phone will generally be in touch with several towers, even though it is only using one at a time for calls etc.

If you have an estimate of the distance from two or more towers you can imagine drawing a circle around each tower with the radius equal to this distance.

Where the circles intersect is the 'likely' position(s) of the mobile device.

WiFi estimation works on roughly the same principles but is much more accurate as there are so many more WiFi networks.

The big data aggregators (Goggle, Apple etc and their partners) receive data from millions of phones which allows them accurately locate where a particular WiFi network is located. When you then ask your phone to check you position they are able to see what WiFi networks you are close to and vey accurately narrow down your position, especially in a built up area with many WiFi networks.

Most phone positioning systems will use a mix of technologies, GPS, cell strangulation, WiFi to help narrow down your location.

Of course if you are on top of a mountain or in desert the options are a bit more limited, and GPS becomes more important...