Maybe I am too strong on Geometry, but how can a weak "other constellation" position improve your GNSS position?
Assume you have 10 GPS and 8 Glonass, what good are 3 Compass and 3 Gallileo satellites in improving your precision? Even with 4 each you are looking at PDOPS in the 5-7 range
Not having full GNSS software, how is the position of various constellations weighted in a final GNSS solution?
How precise are other constellation broadcast orbits and how precise are their related ephemeris? How timely are their post observation ephemeris?
I can imagine that the other satellites are in favorable positions, but imprecise ephemeris could give a mathematically tight solution that is in fact not accurate.
Paul in PA
I thought you were going back to the old days of 8 channel receivers.
If there were 12 birds in view, and one "base" reciever was in the field, it had an alogrithm, to ignore the 4 highest in the sky.
Then 2 more recievers were in the woods. Good sky view, from 30 degrees up from the horizon. This forced it to collect the highest birds. So, it only had 4 birds in common... So, the 2 woods units would fix well. But the one in the field, to the ones in woods, were poorer.
Just depends on their sky view.
N