Product InformationHow do Meinberg receivers handle the GPS Week Number Rollover?
The GPS system time is based on week numbers since an epoch and seconds of the current week. Unfortunately GPS satellites send the GPS week number encoded in 10 bits only, covering a range of 1024 weeks (week numbers 0 to 1023). After week 1023, the week number transmitted by the satellites rolls over to 0.
This is irrelevant for pure navigation receivers, as they only work with time differences. Receivers that derive the current time and calendar date from the GPS data have to take this rollover into account in order to determine the current date correctly.
The "start date" of the GPS system time is Sunday, January 6th, 1980. The first GPS week number rollover took place 1024 weeks later, on Saturday, August 21, 1999, and the next rollover will take place another 1024 weeks later, on Saturday, April 6th, 2019.
Meinberg's approach to handling GPS week number rollovers
Meinberg's approach with their own GPS receivers is to use a 16-bit week number internally, and the week number is simply incremented at the end of each week. So if the week number sent by the satellites first rolls from 1023 to 0, the internal week number simply rolls from 1023 to 1024, at the next rollover from 2047 to 2048, and so on.
More details can be found in the knowledgebase article associated with this topic.
