On Jan 24, 2008, at 1:30 AM, atreau2k wrote:

>
> Anyone have an idea about how to mathematically detect the signal
> strength to determine approximate distance to the nearest network?
>

Free Space Loss = 20 * Log10 (frequency in MHz) + 20 * Log10 (Distance  
in Miles) + 36.6

The problem you have with trying to use signal strength, is that you  
would need to know the signal strength of the transmitter and antenna  
gain, you also have loss from other objects, and interference from  
other devices.  Try using a 2.4GHz device behind a fish tank or next  
to a running microwave.

> Senario...
>
> I walk into a large facility with numerous routers all serving me
> Internet.  I wish to determine my approximate distance to each
> router.  Then using math and most likely packet send and receive
> times, I want to guesstimate the distance to router 1, router 2
> etc..   Very similar to cpt.. cell phone triangulation.
>
> oh.. doing this with a web browser rather than an app would be just
> awesome.
>
> so.. any ideas?
>

The 802.11 protocol was not designed to function with DME capabilities.

You would need access to some pretty low level features of the  
wireless radio and there is no method I know of to send a signal to an  
access point and have it send a return a packet in an exact known  
amount of time.  Given the small indoor area you are asking about, you  
would need a high level of accuracy to make the distance measurements  
meaningful.

If you want to do something similar to cell phone triangulation, then  
your best bet is to do what the cell guys do,  map out the signal  
strengths at various points around the area and use that data to  
construct a map of where you are.  Your map would need updating  
whenever an object in the area moved.

There is definitely no way to do this from the web browser.



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