The GPS 10 bit week counter rollover event

Off Topic
#1

I received the following from Verizon about my phone. Looking at the Verizon link and the further Homeland Security link, I see no info on the severity of the problem and if it is short term or permanent. Any Ideas? Ten bits sounds like planned obsolescence. Verizon offers that a good fix is to buy a new phone.

Starting November 3, 2019, for specific devices sold between 2006 and 2016, users may experience Global Positioning System (GPS) location-related issues due to the GPS Week Number Rollover. Voice, text and data services will not be impacted by this rollover.

GPS accuracy may impact the performance of navigation applications used on these devices. For additional information, please visit verizonwireless.com/legal/notices/global-positioning-system/.

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#2

Luckily since it is only 10 bits, rollover was likely a design consideration when these devices were being made (especially since they were built post-Y2K). I wouldn’t be worried.

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#3

It has happened before in 1999. The firmware of the GPS receiver is responsible for handling the rollover. It’s possible this rollover was overlooked by developers of some GPS receivers. If so then this would be a permanent breakdown unless the developers updated the firmware (highly unlikely for devices that are several years old or more).

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#4

This appears to have already happened back in April. If your GPS still functions accurately then I think you’re good to go. I’m not sure where Verizon is getting the November date from.

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#5

The rollover was back in April, but there have been some secondary isssues with different GPS implementations. I think some flights were canceled last month due to some issues with aircraft GPS software. Apple has been working on updates to previously EOL versions of iOS for this, but I can’t remember the exact date of concern, but it was months after the rollover date, and expected to really mess up the apple gps fixes.

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#6

Apparently some Qualcomm chips have an intentional offset in their calculations, so the 10 bit rollover that other receivers hit back in April, the affected Qualcomm chips will hit November 3rd. These devices have all been created after the first 10 bit week rollover, but the OS code using the chips often was not written to take the second rollover into account.

https://techship.com/news/gps-week-roll-over-issue-during-epoch-restart/a

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#7

That explains the odd date. Well, that sucks for a lot of people. :thinking:

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