GPS systems are actually pretty easily disrupted, whether it be by radio interference or weather outside of our control. For a while now, it has been a concern—especially with federal agencies—what would happen if GPS went down for some reason. While it might not seem like a big deal, GPS is used for many things more important than getting you to the closest Wal-Mart—including keeping time.
The National Institute of Standards and Technology (NIST) and the U.S. Naval Observatory (USNO) have been performing tests alongside two companies, CenturyLink and Microsemi, to see if there is a practical back up to GPS systems already in place so that a disruption wouldn’t effect major systems like timekeeping.
The experiments, which started in April of 2014 and are still going on, work by connecting the NIST time scales located in Boulder, CO, and the USNO alternate time scale located in Colorado Springs. These are two of the federal time scales, located about 95 miles apart, used to make the international standard for time also known as the Coordinated Universal Time (UTC).
The research here is suggesting that time transfer can still be accomplished within 100 nanoseconds if GPS were to go down for some reason, although the experiment itself was a failure as there were some delays in timekeeping. Currently, if a power source went down and a connection needed to be re-established, GPS would be needed to re-calibrate everything as time signals are sent through GPS and then used to sync up cell phone calls, put a time stamp on official occurrences, and help with travel by car, air, ship, or train internationally.
What does this matter to you? Well, while it’s still in early stages, it has been proposed that the experiment could be the basis of a partial backup for GPS, while GPS still detects and fixes any timing delays. Either way, it’s exciting to see advancements in back up GPS research—even if it is just time signals right now.