A team of researchers from the University of Waterloo has created a drone-powered device that can see through walls using WiFi networks.
The device, named Wi-Peep, can fly close to a building and then utilize the WiFi network of the inhabitants to quickly identify and locate any WiFi-enabled devices within.
The Wi-Peep exploits a loophole the researchers call polite WiFi. Even if a network is password protected, smart devices will automatically respond to contact attempts from any device within range. The Wi-Peep sends several messages to a device as it flies and then measures the response time on each, enabling it to identify the device’s location within a meter.