NAVSOP Navigation System Rivals GPS
dangle writes "BAE Systems has developed a positioning solution that it claims will work even when GPS is unavailable. Its strategy is to use the collection of radio frequency signals from TV, radio and cellphone masts, even WiFi routers, to deduce a position. BAE's answer is dubbed Navigation via Signals of Opportunity (NAVSOP). It interrogates the airwaves for the ID and signal strength of local digital TV and radio signals, plus air traffic control radars, with finer grained adjustments coming from cellphone masts and WiFi routers. In any given area, the TV, radio, cellphone and radar signals tend to be at constant frequencies and power levels as they are are heavily regulated — so positions could be calculated from them. "The real beauty of NAVSOP is that the infrastructure required to make it work is already in place," says a BAE spokesman — and "software defined radio" microchips that run NAVSOP routines can easily be integrated into existing satnavs. The firm believes the technology could also work in urban concrete canyons where GPS signals cannot currently reach."
If its just using signal streangth then there are going to spots in cities or other cluttered terrain where it could be innaccurate. It would be ok if there is no terrain to interfere.
Sure in an open area the signal strength from broadcast and third-party location services is fine but so is GPS.
But in an urban environment these are not accurate signal strength is only loosely proportional to inverse square of the distance so any accuracy will utterly break down. I can't see them having the money investing on getting a location DB for coverage outside major cities meaning you have to ship an unusable feature to most of the population.
The firm believes the technology could also work in urban concrete canyons where GPS signals cannot currently reach.
This will only work by regularly updating a database of local signals by driving down these roads and walking around areas. You might get the reliability for a consumer device but SDR like this can hardly be cheap, small and low power.
Possibly they have algorithm to make this manageable but i would think installing purpose built transmitting devices at every street corner would be a better option.
Wow, how short sighted.
They're not trying to replace GPS - it's to augment it when GPS doesnt work. If you have a receiver with both systems you are far more likely to have one of them work, because most of the obstructions for GPS also go hand in hand with the availability of other networks.
Sure it might not work in the middle of the outback, but GPS generally will so it's not the target market.
So your sole criterion for something being completely useless is that it doesn't work 3 hours north of Perth? I look forward to your input when the next article on deep-sea submersibles comes along.
systemd is Roko's Basilisk.