Can a phone GPS partially fail?

[UnderOpenSky]

Seems improbable right, but I'm having some strange issues. I've noticed for a little while that when using Google maps it would put me on the wrong road before correcting itself. When using memory map (OS mapping on my phone) where it could be out or just get no lock for a while. Recently in Turkey it was worse, we were out for a walk and it was consistently out by up to a mile. I've used an app to clear all the GPS data and redownload the AGPS stuff which helped for a bit, but it started doing it again.

Am I going crazy? Is this a thing or more likely a bug on my P30. Either way it's frustrating enough I may have to replace the phone if I can't sort it, but I really don't want to.

 

[killer b]

I have found a few times driving around Manchester recently (specifically when driving out through Salford on the M602) that my google maps thinks I'm on a road running parallel to the motorway - never experienced anything like it anywhere else, so I wonder if it's some sort of local issue (atmospheric conditions confusing the GPS signal or something?)

 

[salem]

Yeah, they use a few different methods to locate you, not just GPS but also by triangulating your position to relative wifi hotspots and mobile basestations that they know the location of so even if your GPS isn't working you can still get some service.

Try the things here - Find and improve your location’s accuracy - Android - Google Maps Help

It's also possible that they just lose accuracy though, my old phone would really struggle and just be inaccurate and it was because of a lose connection inside (apparently common with the model of phone I had at the time) - it didn't always fail obviously but it wasn't reliable at all.

 

[UnderOpenSky]

I have found a few times driving around Manchester recently (specifically when driving out through Salford on the M602) that my google maps thinks I'm on a road running parallel to the motorway

Yes. Definitely how it started.

Yeah, they use a few different methods to locate you, not just GPS but also by triangulating your position to relative wifi hotspots and mobile basestations that they know the location of so even if your GPS isn't working you can still get some service.

Try the things here - Find and improve your location’s accuracy - Android - Google Maps Help

It's also possible that they just lose accuracy though, my old phone would really struggle and just be inaccurate and it was because of a lose connection inside (apparently common with the model of phone I had at the time) - it didn't always fail obviously but it wasn't reliable at all.

Thanks. Tried all those and more. Googled a fair, but couldn't find anything with similar symptoms and did wonder if Google Maps was the most accurate because of other methods.

I'm off to the Scottish Highlands for 4 days walking soon so I'll test it a lot then. There should be nothing else to help it out. I actually had the charging port repaired recently, wonder if that could have done it. Highlands is less of an issue as there will be a few of us with proper maps, but when I'm running on the moors, I use it a lot, so needs to be right. Hopefully it won't another "which new phone" when I get back....

 

[WouldBe]

My sister has shown me her phone while sat still on the sofa and it seems to think she is wandering round the garden or up and down the street. Meanwhile her phone shows her car as being rock solid in the same position.

 

[A380]

Some mapping apps guess that if you are moving at road speed you are on a nearby road.

Less likely but there are a number of different datums in use that can be off from each other by almost 100 m at most. Does your phone have settings and has it been switched to one for a different region from the one you are in. I suspect not because they would probably code it so it took the appropriate datum for where it roughly thinks you are. Might be worth having a poke around in the settings though?

 

[2hats]

Recently in Turkey it was worse

Er... whereabouts in Turkey?

My sister has shown me her phone while sat still on the sofa and it seems to think she is wandering round the garden or up and down the street.

GNSS indicated position will always wander more where the number of fixes (visible satellites) and signal strength is reduced - it's bound to go on a pseudorandom walk inside the CEP (particularly without ionospheric path correction eg SBAS).

 

[UnderOpenSky]

Er... whereabouts in Turkey?

GNSS indicated position will always wander more where the number of fixes (visible satellites) and signal strength is reduced - it's bound to go on a pseudorandom walk inside the CEP (particularly without ionospheric path correction eg SBAS).

In some hills a few hours drive from Antalya.

 

[UnderOpenSky]

Some mapping apps guess that if you are moving at road speed you are on a nearby road.

Less likely but there are a number of different datums in use that can be off from each other by almost 100 m at most. Does your phone have settings and has it been switched to one for a different region from the one you are in. I suspect not because they would probably code it so it took the appropriate datum for where it roughly thinks you are. Might be worth having a poke around in the settings though?

I've had a look at all the settings, plus downloaded a third party app.

In the UK I use OS grid, but suspect the app just converts it.

 

[2hats]

In some hills a few hours drive from Antalya.

That whole region appears to have been subject to assorted GNSS degradation over recent days and weeks.

 

[UnderOpenSky]

That whole region appears to have been subject to assorted GNSS degradation over recent days and weeks.
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Wow, that's pretty interesting stuff. We shall have to see if that was indeed it, but I suspect not.