The GPS is a satellite-based radio-navigation system owned by the US and operated by its Air Force. It works by sending out timing signals and relies on precision timing to operate.
The CBS Local site said GPS sends out timing signals which contain timestamps with a code based on the week and seconds of the week when GPS time began – 6 January 1980.
But GPS time uses only 10 bits to enumerate weeks and the seconds in that week, so it runs out of space after a period of 1024 weeks or 19.7 years.
When the rollover happens this weekend, it could roll back a device to a wrong date, cause critical systems to malfunction due to their being thrown out of sync with time or make a personal GPS device behave in an erratic manner.
The CBS Local site said in future, GPS navigation messages would use 13 bits instead of 10, meaning that the rollovers would take place about every 157 years, rather than 20 as at present.