But it is unknown how many sensors there are in the JLOC system, or how accurately it can determine the location of a jammer.

ECONOMIST: GPS jamming

In America there is already a military system to spot GPS interference: the GPS Jammer Detection and Location (JLOC) system run by the National Geospatial Intelligence Agency.

ECONOMIST: GPS jamming

According to Navsys, the company that developed JLOC, it involves a network of GPS receivers capable of detecting regions of higher than normal signal levels and low signal-to-noise ratios, either of which can indicate interference.

ECONOMIST: GPS jamming