Business Week writes:
Rosum has developed a technology that gets GPS and TV signals to work in sync. With a receiver designed to listen for both GPS and the combined TV-GPS signal, using a set of chips tuned for both, you have a powerful positioning system that can work indoors and show your 3D position, such as what floor of a building you’re on. Already, Rosum’s technology has been tested successfully in the San Francisco Bay Area and in Northeast locations from New Hampshire to Washington, D.C.
To what avail? Since objects and people aren’t always outdoors and within sight of GPS satellites, you need more than GPS. “If you want position navigation everywhere, there is no single system that is going to accomplish that feat,” Spilker says. Unlike Rosum’s new technology, “GPS signals are transmitted with very limited power, so the system simply can’t handle going indoors or underground.”