问题
I am trying to make sense of an inexplicable situation — starting February 15, a remarkably high percentage of the location readings we captured in our app are reporting exactly 10.0m accuracy, which seems strongly correlated with those arriving from a GPS source, as we see it almost exclusively with High-Accuracy and Sensor-Only mode (though there have been occasions where Battery Saving).
After reviewing our system, we don't see any point where we could be introducing this ourselves. It affects all deployed versions of our app.
We have begun to instrument our application to get more metadata, but would love to have a better understanding of how something like this could happen approximately instantaneously, which affected multiple versions of the app at a time when we did not change any running services.
Here area a few potentially-related issues:
- navigator.geolocation.getCurrentPosition in cordova gives only 10 meter accuracy
- FusedLocationApi Performance Issue: Accuracy seems capped at 10.0 meters
- Wierd and very unexpected issue with location.getAccuracy()
- Why does FusedLocationProviderApi never report accuracy better than 10m? Is this documented?
- Cordova geolocation accuracy gets capped at 10 meters
And some graphs to show what we are seeing:
So — has anyone else seen anything similar, or have an explanation as to what might be going on here?
回答1:
it is a Google Play Service issue, reported internally here and it will be fixed from version 13.4.0
回答2:
I am not a GPS expert, but years ago I picked up somewhere that GPS technology is (still) a military technology, meaning that if military purposes require it, civil usage/accuracy of GPS functionality may be limited from time to time...
But this was years ago. Of course (and hopefully) I am mistaken, but just wanted to share this possibility with you.
Edit:
Never mind. After reading this, I understand that this "Selective Availability" feature is abandoned a long time ago.
来源：https://stackoverflow.com/questions/49656301/dramatic-shift-in-location-accuracy-distribution-starting-february-15