WiFi signals could potentially be used to identify people and map their surroundings without relying on cameras or requiring the person being observed to carry a connected device. "By observing the propagation of radio waves, we can create an image of the surroundings and of persons who are present," says Professor Thorsten Strufe from KASTEL, KIT's Institute of Information Security and Dependability. "This works similar to a normal camera, the difference being that in our case, radio waves inst...