TV, Cellphone, WiFi Provide Data For GPS Back-Up

British researchers are working on an alternative to Global Positioning System (GPS) navigation that will function when GPS fails. They say the GPS satellite system might not last forever, and could be damaged by a freak space incident or even a military conflict.

The new system comes from BAE systems, a defense company in the United Kingdom. BAE has for some time been trying to find alternatives to GPS, which works by comparing a device's location to multiple satellites in space.

Solar Flare Could Destroy GPS Satellites

While GPS functions well for now, it is vulnerable to satellite malfunction.

This issue will become more prominent as time goes on, as satellites can be put out of action by mechanical failure, solar flares, or enemy action during war.

BAE's alternative is called Navigation Via Signals of Opportunity (NAVSOP). Like GPS, it uses multiple sources to acquire location information.

But NAVSOP devices only start with GPS signals, to get a general picture of where they are on Earth. Over time, GPS satellites become less vital to NAVSOP functionality. (Source: bbc.co.uk)

NAVSOP takes its updated location data from wireless signals, using sources such as radio and TV broadcast towers, plus cellphone and WiFi networks. It pieces together all available information to determine its location.

Although GPS usually gives a more precise location, the signal from satellites is relatively weak. NAVSOP uses signals that usually travel over a shorter distance, and so are much stronger.

New System Would Combat GPS Jammers

It is also much more difficult for these earthbound sources to be blocked. For example, during a war, the enemy would have to target all radio towers and broadcast units.

NAVSOP might also work in urban areas with lots of skyscrapers close together, a landscape which can sometimes cause problems for GPS.

Researchers at BAE say NAVSOP would be designed only to complement GPS: a back up system, rather than a replacement. They say NAVSOP's big advantage is its infrastructure is already in place.

The main challenge now is to produce compatible receiver and tracker devices in the same small size as GPS chips. (Source: com.au)