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barbeau / gpstest

The #1 open-source Android GNSS/GPS test program
Apache License 2.0
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GNSS lock with only 2 satellites #685

Closed altayhunter closed 3 months ago

altayhunter commented 3 months ago

Describe the bug GNSS is said to require a mininum of 3 satellites to obtain a lock, but I've seen GPSTest obtain a lock occasionally with as few as 2 satellites even from a cold start. Is this somehow expected under unusual circumstances, or is GPSTest mistaken about something?

To Reproduce Steps to reproduce the behavior:

  1. Go somewhere with weak GNSS signal (e.g. indoors).
  2. Run GPSTest for a while.
  3. Under the right conditions it will obtain a lock with just 2 satellites (then typically lose it again immediately).

Expected behavior A minimum of 3 satellites are required for a lock, or maybe no fewer than 4.

Observed behavior Sometimes a lock is obtained with just 2 satellites.

App, Device and Android version: Device: OnePlus 7 Pro GPSTest: v3.10.3 (24097-google) Android: 14 - 20240607 ROM: YAAP-14-Urshanabi-guacamole-20240607 Google Play services: version 24.22.13 (190400-638740827)

Screenshots: Screenshot_20240614-112337_GPSTest

barbeau commented 3 months ago

Thanks for the repot! GPSTest shows the values reported by the GNSS chipset, so looks like there is indeed an error in the values the device is reporting.

Could you please open an issue for this at https://buganizer.corp.google.com/issues/new?component=313183&template=1021001 and include the same info (and link to the issue here)?

I'm going to close this as "Won't fix" here because there isn't anything I can do in GPSTest to fix it.