GPS is one of America’s great gifts to the world — but it’s far from perfect

It’s not unusual for agencies to issue press releases touting their accomplishments, especially when authorization and appropriations bills are being considered.

It is unusual for an industry trade journal which normally promotes the agency’s programs to harshly criticize its public statements.

On June 16, the Air Force issued a press release with the headline, “New reports confirm near-perfect performance record for civil GPS service.” The editor of the industry journal GPS World subsequently wrote a column saying the release “perpetuates a dangerous myth, keeps users in the dark about the actual state of affairs… and abets the lack of political will and understanding of GNSS vulnerabilities.”

{mosads}One problem, according to the editor, is that people tend to read and remember only headlines. The body of the release doesn’t say “near-perfect” and discusses reports that examined GPS performance in 2014 and 2015. “This conveniently draws up short of January 2016, when several GPS satellites broadcast a timing error that triggered equipment faults and failures globally for nearly 12 hours. Thus demonstrating something far from perfection,” he wrote.

Another, perhaps more concerning, problem is that even if the Air Force’s portion of GPS does perform perfectly, its responsibility ends when signals leave the satellites. Before getting to users, signals can be disrupted or degraded by all kinds of things. Personal privacy devices, other kinds of jammers, spoofers, solar activity, malfunctioning electrical equipment, and even the local geography can significantly degrade or disable a receiver’s performance.

Yet overconfidence has caused people to follow their receivers’ directions without question, driving into lakes and subways, and getting into sometimes fatal accidents. A government pronouncement that reinforces such overconfidence “perpetuates a dangerous myth,” the industry journal editor continued.

GPS is America’s gift to the world. Its timing and location signals have come to undergird virtually every technology. It has made our world immeasurably more efficient and convenient. But its weak, easily disrupted signals must be protected much more than they are now.

The nonprofit I work for, the Resilient Navigation and Timing Foundation, supports policies and systems that help make GPS and its users much less vulnerable to errors and disruptions. These include protecting the GPS frequency by not allowing interfering transmissions, toughening user equipment with better software and antennae, and augmenting GPS satellite signals with those from a high power complementary and backup terrestrial system such that the resulting combined service would be exceptionally difficult to disrupt.

These recommendations have all been mandated by presidential directive, supported by government studies, and endorsed by the National Space-Based Positioning, Navigation, and Timing Advisory Board. Every public official I have spoken to agrees that they should be implemented. Yet, because GPS is widely perceived to be “near perfect,” there has been no impetus for action and little has been done.

A significant GPS fault or disruption could be disastrous for America. I hope the administration and Congress will act to protect GPS and its users before the nation has more dramatic demonstrations that the GPS satellite signal system is far from perfect.

Dana Goward (@GPSBackup) is president of the Resilient Navigation and Timing Foundation and a member of the administration’s National Space-Based Positioning, Navigation and Timing Advisory Board. Until 2013, he served as the nation’s maritime navigation authority with the Coast Guard. He is cited in the GPS World editorial on the Air Force press release.

The views expressed by contributors are their own and are not the views of The Hill.