Threats can imperil satellite navigation systems.
Satellites provide essential navigation services, but threats exist to their operation. Radio interference from both natural and human sources presents serious problems for the system’s myriad users. Engineers and scientists continue to develop solutions to ensure the continued operation of global navigation services.
Solar activity can interfere with satellite signals. Solar storms occasionally interrupt clear reception of signals from space. Those who design satellite systems must plan for these disruptions and be aware of how solar activity varies with the 11-year sunspot cycle.
The successful operation of a satellite navigation system requires around-the-clock monitoring of the satellites’ health and the periodic replacement of older satellites. The process is labor-intensive and expensive and requires multiple backups to ensure continuous operation.
Man-made Radio Interference
GPS and other satellite positioning systems were designed to use quiet parts of the spectrum. However, these channels face the danger of being overwhelmed by communications signals from other nearby frequencies. Engineers must test the possibility of interference from multiple systems.
Although their use is illegal in the United States, portable GPS jammers are traded clandestinely and used by those who wish not to be tracked or otherwise located by GPS. These devices cause nearby navigation systems to malfunction, potentially threatening public safety.
System Under Attack
The increasing reliance on navigation satellites for military and commercial activities makes them a tempting target for an enemy. While it is difficult to disable the satellites themselves, these and other GPS components must be protected from interference or attack.