You Saw This In Dark Knight, Now See The Real Thing. App Lets You See Through Walls
Can Wi-Fi let you see people through walls? yes it definitely can. Wi-Fi is a signal, basically like a sonar that bounces off of every thing it encounters, as we saw in the film the Dark Knight.
Researchers at MIT have developed a sensing technology that uses low-power Wi-Fi to detect moving people behind walls. The system is next gen technology compared to other wall-penetrating radars that utilize heavy equipment.
The Wi-Vi system by Dina Katabi and Fadel Adib sends out a low-power Wi-Fi signal and tracks its reflections to sense people moving around, even if they’re in closed rooms or behind walls. The MIT system can be set to view or ignore stationary objects or simply focus on moving people . It can determine the number of moving persons in the room and their relative locations.
The system sends out two nearly identical signals, but one is the inverse of the other, and thus they cancel each other out. “So, if the person moves behind the wall, all reflections from static objects are cancelled out, and the only thing registered by the device is the moving human,” Adib, a graduate student in MIT’s Department of Electrical Engineering and Computer Science, was quoted as saying in a release.
The Wi-Vi receiver uses changes in the signal reflection time to calculate where a moving person is behind a wall. It can also detect gestures such as arm waving and could be used to control home lighting or appliances in another room.
It could also let people communicate with the outside using hand signals alone. British researchers have also been investigating how to use Wi-Fi for surveillance and urban warfare, but the MIT system could be used in applications such as search and rescue, law enforcement, or personal security.