I was visiting local NTRIP caster, but they don’t have any explanation about what can cause trouble. We tried to measure points with different GPS systems (you can find results in this topic: Comparison between Emlid Reach RS+, Leica, Altus and Trimble receivers - #5 by michaelL), but results showed no shift from original coordinates. Now I don’t have too much time to experiment, but I still have to try to do the same approach, but for static points. Basically, the workflow should be as following:
- Measuring static point in RTK mode with logging turned on.
- PPKing collected log and comparing results with RTK measurement.
Measurements should be the same.
With our local NTRIP caster we have different correction techniques:
- SITE - corrections are received from nearest station
- NETW-MAX - corrections are being received from nearest station + 4 stations around the point
- NETW-iMAX - corrections from nearest station + 4 stations around, but modelled for the point, where the measurement is taking place
- VIRTUAL-RS - NTRIP caster is placing a virtual base station near the rover and modelling the corrections.
I had good results with VIRTUAL-RS, but with NETW-iMAX I had the issues, which were described in this topic. Maybe, it is the correction issue. It would be nice to compare the same results for all correction methods. I have 4 Reach units (2x Reach RTK kit and 2 Reach RS+). If I will connect them all to the one WiFi and place them on some kind of a rig, I could run simultaneously all 4 RTK correction methods.