Pretty neat, use TV signals to locate an object the same way GPS works, and do it on a $40 chip!
…realized a synchronization feature in digital and analog television signals could be used for other purposes than to lock the vertical hold for older TVs.
The engineers created a radio receiver chip that could zero in on the TV signal and get the synchronization information. Using precision timing, they figure out how far a TV signal travels before it is picked up by a device equipped with Rosum chips. Next, they compare the measurements against other data that they collect with their own listening stations and then finally calculate the device’s position. The Rosum engineers call this process “multilateration,” which is akin to navigational triangulation.