I normally use an internet-based NTRIP correction service, which I configure directly on my DJI RC. I connect the RC to my phone hotspot.
Currently, if I’m in an area with no phone signal, I use my D-RTK2 base station as a fall-back, although this gives me relative accuracy that’s fine for my use-case.
I have the RS3, which I always use to shoot GCP’s if needed. I also understand I can use this as a base station, on Local NTRIP, to stream corrections to the RC, instead of the D-RTK2. The issue there is that it’s not always possible to stay close to the base station; often I will follow the drone to stay within VLOS. The D-RTK2 can cope with being a good distance away.
My question is around using the RS3 to stream corrections, when connecting it to the internet for an NTRIP service. I don’t understand why I would do that, when I can connect the drone RC directly to the same NTRIP service. Both options need either a dongle or a phone hotspot. Isn’t this just adding an extra ‘point’ through which the corrections need to flow?
I must be missing something, so it would be great to hear your thoughts and experience!
However, with an NTRIP service, you do not have control over the baseline. In some cases, your drone might be quite far from the nearest NTRIP base.
Also, outages can happen, so having your own base gives you more flexibility and independence, allowing you to work without relying on external services.
Correct. You would need to keep the RC, the RS3 and your hotspot all within local wifi range of each other.
The first 2 questions I commented on were in relation to using Local NTRIP. In those cases, no internet (cellular data) connection is required.
This question is now back to when there is cellular data available. To your question. The advantage of using a local base, as with the RS3, rather than a network NTRIP connection is that your baseline, the distance from the base to the rover, can be considerably less, depending on where the network base is located. And therefore, the corrections are superior.
If you have cellular data available, you can use the RS3 to collect a point via NTRIP to the network CORS. After a point is established, you then change the role on the RS3 to a base by using that point you just established as a manual point, and then are able to send corrections to the RC with a much shorter baseline. If you want to wander off and follow the drone, then Local NTRIP will not work for you. But you can use EMLID caster to send corrections so long as you have a cellular connection at the RS3, and the RC as you move around.
Is it worth it? That depends on how far away your CORS is, your error budget, and the time you have on site.
