Analyzing a More Resilient National Positioning, Navigation, and Timing Capability

Because of the widespread use of the Global Positioning System (GPS) for positioning, navigation, and timing (PNT), concerns have been expressed that a disruption of GPS might require a national investment in backup capabilities. The authors assess the costs associated with realistic threats to domestic, nonmilitary uses of GPS, and review possible additions to the PNT ecosystem in light of those costs.

When the ability of individuals and organizations to adapt to and use existing alternatives and workarounds is taken into account, our analysis suggests that the costs of GPS disruption, while real, would not be as high as is sometimes assumed. When actual GPS jamming events have occurred in the past, users have felt the effects but generally managed to cope without disastrous consequences. Also, we consider it unlikely that any event short of nuclear war would deny all satellite navigation to the entire United States for more than a few days. At the same time, any system that could entirely replace GPS would be comparatively much more expensive than the damages it would mitigate.

Therefore, it is difficult to justify extensive investment in more GPS backups, although industry or government might well invest in PNT systems for their other merits, not just as a backup for GPS disruption per se. For example, the federal government is already investing in a system that will improve PNT for phone users in important urban areas, and this incidentally could also serve as a GPS backup.