This radio mast on a Norwegian island sent out positioning signals until 2015 Torbjørn Kjosvold/Norwegian Armed Forces
AS FAR as Logan Scott was aware, the date was 28 September 2017 and he was at a conference centre in Portland, Oregon. But that was not what most of the smartphones around him seemed to think. Many of them were displaying a location somewhere in Europe. Others were saying it was January 2014 and refusing to send texts or emails.
Fittingly, the conference was about global navigation, and the problems began as Scott was presenting a talk on how GPS receivers can be fooled. He borrowed a detector and tracked down the source. It turned out that a GPS signal generator used for testing had not had its terminals properly capped.
The mistake was soon put right, but a deliberate attack could be far more destructive. GPS, originally developed by the US military for defence purposes, is now used for everything from power grids to financial trading, ambulances to air traffic control. To reduce the risks of relying on it, the European Union is building its own satnav, Galileo, a system that has become a political football in the UK’s negotiations to leave the union. But perhaps backing up satellites with more satellites isn’t such a stellar idea. Instead, a more down-to-Earth technology, with its roots in the second world war, could be re-enlisted in our defence.
We have become used to the power of satnav. Pull out your phone and it will give you your position in seconds. To reach this nirvana of navigation we …
