HOME BLOG SHOP FORUM CONTACT US TERMS

Performance degradation when not in RTK mode

Why does the Alpha performance degrade so much while Fix=5 and Fix=2?
I compared it simultaneously with a Ublox 7 device with Fix=2. The rover was in motion.
The x axis represents sample number and the y axis represents distance north of the base station in feet.
See the figure below:
53%20PM

Might be RTK implementation related, optimizing for faster RTK convergence while sacrificing other non-related modes behavior.

I am having trouble maintaining an RTK fix. Sometimes I lose RTK fix because my NTRIP client loses connection, sometimes frequently. But I lose RTK fix for some other reason more frequently. My application is a steering control application for agriculture and it can’t tolerate losing RTK fix especially if the performance degrades so suddenly during the FloatRTK fix and the DGPS fix. What percentage of the time can I expect an RTK fix? One day it looked like I had 90% RTK fix time. The next day it was less than 10% on the same route. The NTRIP client was not losing connection during this test. What are the reasons for RTK fix time differences?

As GPS+GLONASS has 10 ~ 16 satellites above 15 degree elevation angle across the day at your location, some planning on what time of day to use RTK to avoid low number of satellite which is difficult to get RTK Fix and more easily losing RTK Fix is needed, also avoid time of day with high ionospheric activity.

Use Trimble GNSS Planner: https://www.gnssplanning.com/#/charts, avoid 11:30AM in below case.

The # of satellites is less easy to see, so I prefer using GNSS Radar or GNSS View

Avoid 4:30PM when satellites number lower to 10

12:00 ~ 14:30 having 13 ~ 15 satellites seems a good period.