Rosum TV-GPS triangulates urban & indoor position from TV towers

California company Rosum have developed a way of triangulating location based on digital, analog and mobile broadcast TV systems, which they claim is capable of working not only in dense urban areas but indoors.  The technology – which can be deployed on its own, or coupled with traditional GPS in a hybrid system – relies on TV signals having a greater transmission power advantage over GPS, together with frequencies that are capable of penetrating buildings.

Unlike the signals from GPS satellites, which by the time they reach ground-level are relatively low power, TV-GPS signals are on average 40dB: around 10,000 times stronger.  Meanwhile unlike GPS, which uses high frequency signals, TV transmitters use the low 50-750MHz bands, allowing them to travel through walls and therefore provide a fix indoors.  Finally, the spectrum used in TV is broader, giving more signals for the Rosum system to choose from.

The hybrid system uses traditional GPS in open areas and TV-GPS in urban ones; an alternative hybrid uses cell tower triangulation together with TV-GPS.  Rosum was founded by the co-architect of the original GPS system, while his colleague on that project sits on the Rosum board of technical directors.  There's no word on which manufacturers may have signed up to use Rosum, but if the system delivers what it promises you can bet we'll be seeing it in mobile devices.

[via NaviGadget]