You might be knowing that Wi-Fi can pass through walls and it helps us browse the web by sitting in any corner of our home. But, what if you can use this ability of Wi-Fi to scan the areas beyond the walls and get an idea of what’s there?
All of the microwave radiation coming out of the router doesn’t make it to our phones, laptops, and tablets. Instead, they bounce off different objects. Using this property, German scientists have found a way to take 3D pictures or holograms of objects inside a room, from another room.
It’s not a new concept. In the past, we’d written about another research that used this property of Wi-Fi. The new method was developed by Philip Holl and Friedemann Reinhard of the Technical University of Munich. “The past two years have seen an explosion of methods for passive Wi-Fi imaging,” says Holl.
Using two antennas, they record a Wi-Fi field surrounding a particular room. These antennas are used to capture the intensity and phase of the field, both from source spot and places it bounces off.
As a result, one gets a holographic image of the room which can be used in different kind of applications. It can be used in rescue operations after a disaster like an earthquake or an avalanche.
Such developments are also bound to make things unsettling for some people as it could open new privacy exploitation issues. The researchers are aware of this threat. However, Reinhard said in a press release: “It is rather unlikely that this process will be used for the view into foreign bedrooms in the near future. For that, you would need to go around the building with a large antenna, which would hardly go unnoticed.”