[time-nuts] GPS Weekly Rollover Fail

[Bob Betts]

Hello All:
Just curious, but is this just a known routine bug that is methodically dealt with or is there a more serious problem in the system(s)? 

Here's the quote from a notice at www.gps.gov

Thanks,
Bob, N1KPR

<https://www.gps.gov/governance/advisory/meetings/2017-11/powers.pdf>
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Failure: April 6/7, 2019

•UTC timing displayed and/or time tags of receiver data containing PNT information could jump by 19.7 years, resulting in system failures
•Any month/year conversion could also fail•Navigation solution should be OK since GPS time is internally self consistent, but associated time tags could be incorrect thus corrupting navigation data at the system level•And the failure is not limited to April 6/7 2019
•A common fix for week number ambiguity was to hard code new pivot date, which shifts event to unknown date/time in future.

–December 2014, older legacy USNO monitor receiver failed
–Feb 14, 2016 Endruntechnology receivers using a Trimble GPS engine failed
–Aug 14, 2016 Motorola OncoreUT+ older firmware failed
–July 22, 2017 older Novatel GPS engine failed, notice was posted in Spring 2017 to upgrade firmware, but many did not check




NOTE Pls add backup address to your phone book: rwbetts at yahoo.com

http://www.bobsamerica.com  http://www.youtube.com/n1kpr 

Engineering: Where Enigma meets Paradox