Turns out WiFi is good for more than just sharing cat GIFs with your friends. Researchers at the Mostofi Lab at UC Santa Barbara have created a system that "sees" inside buildings using two drones and WiFi.
To pull this off, the drones are each equipped with WiFi transceivers and fly in tandem outside the target building. One of the UAVs then transmits a WiFi signal while the second one reads the corresponding received power. Throw in a bunch of advanced math and the data is translated into a 3D image of the internals of the building with some impressive results.
The Mostofi Lab is no stranger to using radio waves to penetrate walls. In 2010 it published its first demonstration of imaging using WiFi. "However, enabling 3D through-wall imaging of real areas is considerably more challenging due to the considerable increase in the number of unknowns," professor Yasamin Mostofi told UCSB's The Current.
This research could help emergency response teams do sweeps of buildings without putting first responders in unnecessary danger. The lab also noted it could be used for archaeological and structural monitoring.