The Challenge
Many modern navigation systems rely on Global Navigation Satellite Systems (GNSS), the most commonly used being GPS. GPS provides precise timing from several satellites to a user, which then allows the user to pinpoint their position. This is continually being updated to allow directional navigation and online mapping to be provided, much like what can be found on many mobile phones. However, there are methods that can either jam or spoof this data, meaning the exact location is unable to be shown or misrepresented.
Traditionally, there are methods to pinpoint your location manually using physical maps and a compass. You would look for landmarks and plot them on the map so you can estimate where you are and the direction you’re facing. However, this can be a particular problem in inclement weather, reduced visibility or environments where there are no visible landmarks, such as high altitudes or under water.
The solution
There are multiple solutions we’re exploring, including map-matching techniques that can help our customers pinpoint a location when the odds would usually be against them. The Earth’s magnetic field and its gravitational pull, acts as a near unique reading depending where you are. You cannot spoof or block these readings, so if you can find a method to read them locally, you can pinpoint your location regardless of interference or visibility – something that can be the difference between mission success or failure, or even life and death. That’s exactly what we’re exploring at the University of Strathclyde: reading magnetic fields, and with the University of Birmingham, looking at the gravitational field readings. In both cases this is being done by measuring quantum effects at an atomic level. In the gravitational field case, we are cooling the atoms to near absolute zero using lasers.
As well as being used for map-matching, cold atom systems can be used as high accuracy inertial sensors and gyroscopes. Due to the fundamental nature of the atoms, very low drift systems can be made. If you know where you start from, these sensors can give you precise location using dead-reckoning, not currently practicable for defence.