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Re: [Full-disclosure] Wi-fi. Approaching customers


I guess you could only meaningfully compare signal strengths as seen at
different points, as at light speed the delays wouldn't be measurable
with any sort of accuracy.  (If you could measure the delays you'd be in
great shape - that was used in WWI to pick out the location of gun
batteries, just using two mics and very accurate timers.)

This trick is called "timed difference of arrival" and is one of the two methods (the other being GPS) to locate cellphones for e911.

Celluar companies have been doing the TDA trick for years to locate stolen/cloned phones. With modern DSP equipment and an antenna array whereby the elements are seperated by an interval based on wavelength (usually 4 antennas) it's not all that difficult.

LoJack also does it this way, although on a much lower frequency.

~Mike.
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