MIT researchers use Wi-Fi to recognize people through walls

All of a sudden, tin foil hats get a whole new meaning.

Is there something special about the WiFi spectrum that makes this work? Does it work with any ambient radio frequency noise?

Is there a reason why very little information showed up from the legs? Are jeans just great at absorbing but not reflecting wifi signals?

We had a wifi radar at school. Was scary good. Only downside was that it jammed wifi for half the engineering building

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what happens when two person stand behind one another. keeping their bodies close to each other. Is there is any way to detect how many person are actually standing there?