GPS “rollover” event on April 6 could have some side-effects

Michal Fludra/NurPhoto by means of Getty Images


On April 6, the Global Positioning System will reach completion of a period– or more properly, a date. That’s when the Coordinated Universal Time (UTC) clock utilized by the satellite navigation system will reach the limitation for its 10- bit “week number” (WN) counter and turn back to 0000000000.

GPS time is connected to the main UTC clock time offered by the United States Naval Observatory. However the GPS variation of the clock tracks the date by counting the variety of weeks given that the start of the present GPS “date”– August 21,1999 So as the clock reaches midnight tonight on the prime meridian, the GPS calendar will unexpectedly end up being 20 years out of date.

This needs to not come as a surprise for many more recent GPS navigation systems. There has actually been a lot of caution– GPS went through a comparable flip as soon as prior to. And the Department of Homeland Security’s National Cybersecurity & Communications Combination Center provided a caution in April 2018 that this rollover was coming, as it will every 1,024 weeks– up until the modernization of the GPS constellation is total, and after that the WN counter will be increased in size to 13 bits.

The majority of more recent GPS receivers will shake off the rollover since they have actually been set to accommodate the date modification. However older systems will not– and this might show to have some intriguing side-effects, as timing information unexpectedly leaps by 19.7 years. The clock modification will not straight impact area computations. However if GPS receivers do not effectively represent the rollover, the time tags in the area information might corrupt navigation information in other methods.

However navigation isn’t the only issue. There are numerous systems that utilize the time for other functions– cellular networks, electrical energies, and other commercial systems utilize GPS receivers for timing and control functions. Given that a number of these systems have exceptionally long lifecycles, they’re the ones more than likely to have actually not been upgraded.

The rollover concern isn’t restricted to one day. Due to the fact that of the method some makers represented the rollover date in the past– by hard-coding a date correction into receivers’ firmware– their systems may stop working at some approximate future date. Some have actually currently yielded: in July of 2017, an older NovAtel GPS system stopped working, and while the business provided a notification months previously cautioning users to update firmware, numerous stayed oblivious of the notification up until it took place. Motorola OncoreUT+ systems and some receivers utilizing Trimble’s GPS engines likewise have actually stopped working over the previous 3 years for comparable factors.

If you have a GPS receiver embedded in anything you own that has actually been around for a couple of years, do yourself a favor today and look for a firmware upgrade.