Help needed - GPS glitches and GSF

Hey all,
We’re experiencing lots of GPS glitches, this is while using GSF since we do not have a compass onboard.
This happens with two different drones, so faulty hardware is not an immediate suspect - except for the hardware models themselves.

HDop and SAT count are OK, but the drone isn’t capable of maintaining position and.

Adding logs here, please let us know if you see anything

Try reducing the number of GNSS constellations to the most useful ones in your region.

Thanks, I saw this mentioned a few times around the forum.
So too many satellites is overwhelming for the MCU running Ardupilot or for the GPS?
The MCU on the flight controller is not the state of the art: OmnibusF7V2 STM32 F745 MCU.

I wonder if it is possible to do so automatically (measurement based, not region based).

I do see some jumps in the GPS.Delta log parameter corresponding with the glitches.

The autopilot doesn’t care how many satellites are in view - that doesn’t increase processing load on the board itself. The glitches potentially occur when the satellites in view change often, resulting in spikes in estimated position.

And you can absolutely derive the best constellations by measurement if the GPS can be connected to software like uCenter. You simply look for the constellations with the most numbers of satellites at the highest signal strength (40dB, min, as I recall). Pick 2-3 constellations and mask the rest.

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Thanks, I’ll try to do the masking. I don’t I’ll be able to use uCenter since we weren’t able to connect via the serial pass (and we don’t have a USB-Serial adapter in hand currently).

I was wondering whether it’ll be possible for Ardupilot to automatically mask the constellations used, just a thought.

Hey , do you have any clue how to fix the issue of GPS NO FIX , even if test was done outside with a clear view to the sky . but unfortunately it still the same result

Seems unrelated to this post.
You should create a new post, and don’t forget to mention hardware used, and other useful information such as satellite count.

I did it 3 days ago , no answers received : GPS NO FIX / test done outside with a clear view ( aerodrome space)