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Regarding the GPS weeks rollover which took place on April 06th 2019. all the websites are talking about the phenomenon but they are not explaining what are the side effects on end users devices if the week number will be 0000.

How an Android smartphone GPS users could be affected regarding this rollover from 1023 to 0000 weeks ?

Regards

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From what I know the rollover is not the only problem, also an additional week counter 13 bits is introduced. A new data format (with larger data) can of course cause problems if unsupported by the GPS receiver firmware.

Also I have read that some GPS devices use the week counter for plausibility checking of the received data. If the week is smaller than the manufacturing week the data have to be invalid so the simple but bad logic. After the roll-over it will simply reject all incoming data as the receiver thinks that the received data is invalid (e.g. because of radiointerference).

  • "the week counter is increased..." makes it sound like the 10-bit week code is changing. That's not happening. The legacy (ICD-200) message continues to encode a 10-bit week number. There are additional messages (such as in the CNAV data) that transmit a 13-bit week number for newer equipment to read. There's no compatibility issue for older equipment. – BowlOfRed Apr 8 at 4:02
  • @BowlOfRed Theoretically you are right, however programmers often develop such bad code so that any changes (even those already described in the standard) can and will lead to program failures even if it should continue to work without problems. – Robert Apr 8 at 6:35
  • I'm unaware of any changes to the data format related to April 6. The 13-bit week number data format has been broadcast in CNAV packets for several years (but only from newer satellites). GPS III sats will also be a change, but none are marked operational yet. – BowlOfRed Apr 8 at 7:27
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The problem on my device (old Samsung xCover2) is that GPS tracks recorded after April 6th, 2019 have an invalid date.

Check out "GPS Test" app from Google Play to see what date/time your device reads from the GPS system. For example on my phone on April 17th, 2019 it displays September 1st, 01.

Different applications will interpret it in different ways so in other applications you might see dates in 1099 or 2099 or 2999 year etc.

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