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WAAS G-III Reference Receiver User Manual Rev 1
Foreword
Compliance with GPS Week Rollover
The GPS week rollover issue refers to the way GNSS receivers store information regarding the current GPS
week. According to the official GPS system specifications document (
ICD-GPS-200
, paragraph 20.3.3.3.1.1),
"… 10 bits shall represent the number of the current GPS week…". This means the GPS week is represented by
an integer number between 0 and 1023. As GPS time started on Sunday January 6, 1980 at 0:00 hours, week
1023 ended on Saturday August 21, 1999 at 23:59:59.
In accordance with the GPS system specifications document, NovAtel G-III Reference Receiver firmware
resets the receiver's GPS week number back to zero. Users should be aware of this issue and keep in mind that
there may be a compatibility issue when purchasing and using different makes of GNSS receivers.