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MIT Researchers Can See Through Walls Using Wi-Fi
itwbennett writes "MIT Professor Dina Katabi and graduate student Fadel Adib have developed a system they call Wi-Vi that uses Wi-Fi signals to visualize moving forms behind walls. How it works: 'Wi-Vi transmits two Wi-Fi signals, one of which is the inverse of the other. When one signal hits a stationary object, the other cancels it out. But because of the way the signals are encoded, they don't cancel each other out for moving objects. That makes the reflections from a moving person visible despite the wall between that person and the Wi-Vi device. Wi-Vi can translate those faint reflections into a real-time display of the person's movements.'"
It's not exactly new either. The only difference here seems to be that the radar signal source is just a low power wifi AP. Yawn.
The paper http://people.csail.mit.edu/fadel/papers/wivi-paper.pdf
You can have your god back when you are old enough to handle the responsibility.
How is that? They are entirely trustworthy; they do what we tell them to do. We gave them every bit of authority they use to spy on us. We threw our privacy at them and cried, "Take this! Save us from the terrorists and spy upon us!"
who prays for Satan? Who in 18 centuries has had the humanity to pray for the 1 sinner that needed it most? ~Mark Twain
I am sure they are using the same frequencies as wi-fi. But wi-fi is not just the use of a certain frequency range.
Troll is not a replacement for I disagree.
When it comes to viewing the movement of humans through walls, there have already been infrared cameras for years, which in most situations will do anything this wifi approach can do and more. The only real advantage of this wifi approach is that it's cheaper, using ubiquitous commodity hardware.
So when it comes to government agencies, this doesn't really change the technological situation: they've already had the ability to track movement through walls for years. They're only restricted in using it to the extent that legal restraints are successful. For example in Kyllo v. United States the Supreme Court threw out a conviction that was obtained in part by using infrared cameras to look inside a home without a warrant.
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
It can't see you if you don't move.
I eat only the real part of complex carbohydrates.
Ya :( This was better http://hackaday.com/2012/12/18/build-a-360-synthetic-aperture-radar-with-mits-opencourseware/
You can have your god back when you are old enough to handle the responsibility.
While it's nice projects like this open up such technologies to hobbyists, the article is documenting something very novel. Traditional RADAR has trouble seeing through walls, as it cannot filter out all the noise from the wall's reflection. By sending two specially encoded signals that cancel each other out against stationary objects, they've sidestepped this issue entirely, and come up with something brand new. They've developed the much wanted Sci-Fi trope of a portable motion detector.