The ANAFI has a commercial grade GPS, where up to 3 m deviation isn’t uncommon. According to the spec in the white paper on page 10, it should be “1.2m standard deviation”. In real life this accuracy will depend on many factors, especially if you are on the ground near cliffs or tall buildings etc that can affect the signal from the satellites.
Edit: This link gives a few clues to how GPS works and what impacts accuracy:
Note that signals from satellites are aimed to be equal or less than 2m (but typically less). A device can’t be more accurate than the signal, unless you go for a high end solution using RTK / PPK technology.
Superb reply sir, thank you very much, PPK/RTK is what I need. Unfortunately, I have no any knowledge about this, if I need to apply them with my parrot anafi, what should I do, if you can guide me or any suggestions are welcome, In the meantime, I'm go studying of it, thank you so much again sir.
I'm coding with parrot anafi via its own SDK (Olympe - Python controller library) but the main problem is too inaccurate GPS that I mentioned above, i just need to improve its accuracy to be less than 10 cm. if its possible, so your reply before is very clear for the first questions, now I just need to figure out the way to apply RTK, but for now, I'm not sure about what sensors, controller, any equipment require for that.
In that case, I don’t think RTK/PPK is the solution for you, as these correction techniques applies mostly for photo-position for more accurate drone mapping, and require drones that are compatible with the technology. The Anafi is not.
It is also very expensive and require a base station in addition to the drone.
For that kind of precision, I would suggest relying the downward facing camera - I.e. having a ground that is easy for the drone to navigate visually.
I’m not an expert though, the people at the Parrot developer forum might be more helpful.