[ntp:questions] Start of new GPS 1024 week epoch

John Hasler jhasler at newsguy.com
Fri Aug 16 12:02:45 UTC 2013


David Taylor writes:
> A pity that they haven't been able to find two or three spare bits to
> reduce the 1024 week ambiguity to nearer a half-century or even 100
> years.

>From the Wikipedia article:
  
To determine the current Gregorian date, a GPS receiver must be
  provided with the approximate date (to within 3,584 days) to correctly
  translate the GPS date signal. To address this concern the modernized
  GPS navigation message uses a 13-bit field that only repeats every
  8,192 weeks (157 years), thus lasting until the year 2137 (157 years
  after GPS week zero).
-- 
John Hasler 
jhasler at newsguy.com
Dancing Horse Hill
Elmwood, WI USA



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