This is setup on one of my back property corners:
This is straight overhead:
Over the years I've tried to get a verified point on this corner and never been able to do so using GPS and Glonass alone. Today, within just a few minutes I had my first point and a few minutes more I had a second. So far, I've been running for about 2 hours and I have 7 points collected. That averages out to about 18 minutes per point, which in this environment is incredible. All seven points are within a few hundredths of each other with no bad points collected (so far) but the test continues, so we'll see if this holds up.
As you can see from the pictures, the challenge for this point isn't just the trees, but the type of trees: mostly pine. For whatever reason, as many of you have experienced, pine canopy is difficult for GNSS work. It has been possible for several years to work around a few scattered pine trees but a pine forest, such as this, is usually a dead end.
I'll keep working with different profile settings, but for this one, I've setup up with verify with V6 resets on, a confidence of 1, minimum engines 1, a minimum phase 1 duration of 180 seconds, minimum epochs 1, minimum duration 0, no validation. What does this mean in practice?
When the start button is initiated (either by the user or in this case, by auto start), phase 1 is started, waiting for a fix, logging that fixed epoch, then resetting the engine(s) that provided it and repeating. The minimum number of fixes in the group is 2 in order to satisfy the confidence of 1 (one fix gives a confidence of 0, a matching fix gives a confidence of 1). However, by setting the phase 1 duration to 180 seconds, the software remains in phase 1 even after achieving a confidence of 1 or more. Until the group has a duration of 180 seconds, the software will not move to phase 2. Once the software passes phase 1 (with 2 or more fixes and more than 180 seconds between those fixes) then it proceeds to phase 2 to get 1 epoch (the minimum required epochs). So, in theory, the point could store with only 3 epochs. While possible, it is unlikely this will happen very often. There will probably be several fixes in phase 1 that will fit in the group before the 180 seconds is acquired, so it could have several more epochs in the solution, but this test is less about building precision (which would happen with more epochs) and more about generating accuracy, i.e. reliable fixes, which from my experience only occurs with time - specifically the 180 second rule.
We'll check in on the test more and provide some detailed statistical analysis later on. But for now, I'm really pleased with what I'm seeing.