determining your location using ONLY wifi signals?

Question

i will be working on a project that tries to determine your position using the wifi signal strength from a few access points. i was wondering if anyone knew of any similiar

Answer 1

Skyhook springs to mind. It depends on people registering the llocation of their APs though.

Answer 2

Goto Wifi in positioning System(WPS), where we use multiple Wifi AP to track a location.. this is implemented by many systems like Google, horizon etc by providing extra security 4 privacy.. I too without knowing this tried on immplimenting this sort of technique.. All d best, we can simplify its complexity by various methods there-by achieving INNOVATIVE to existing infrastructure. I recommend u to go to the wifi router add-in management & usage before pursing this.

Answer 3

I wouldn't have thought that signal strength would work well: too many things interfere with it (like walls). But you might try measuring ping times, especially if you threw a hundred pings at the AP and took the average. Most of the time will be the AP digesting the ping and generating the pong, but there will also be a time-of-flight component for the signals. If the AP response time is consistent then you should be able to subtract it and hence compute the distance to the AP. By well-known hyperbolic maths you can then find your position from 3 or 4 APs.

Paul.

Answer 4

you can try FIND3 project, here's a documentation https://www.internalpositioning.com/doc/, it's API can be used for that purpose and use learning algorithm to constantly learn your position with accuracy. They also have mobile apps (for android only). I'm looking to do something of the same nature.

Answer 5

We did this on a project already determining distance from Access Points, but without the signal triangulation (already covered on other answers here).

I do have a recommendation from the "man, I wish I didn't have to go back and do this" department - it would be to spend extra time on 2 areas:

1. An easy and repeatable method of calibration using Multiple Data Points. For example, the dropoff from being "very close" to "kinda close" will be a lot more than "really far away" to "really really far" away. It's not going to be a linear slope.
2. Data Smoothing. As you move, the signal strength will vary unproportionally to your movement (due to obstacles in the path). It will make your results much more accurate if you take a rolling average of the last 5-10 samples of the signal strength rather than just taking the last sample.

Answer 6

You might like to look at the Google Gears Geolocation API. I don't know how easy it is to use from C#, but it may be useful/relevant.

(Disclaimer: I work for Google, but haven't had anything to do with the Geolocation API.)