[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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