Do I understand this correctly for a two RS3 base - RTK setup?

Goal is to have a precise RTK positioning without any internet in remote locations where I can’t access an NTRIP service.

If I purchase a second RS3 and I set them both up. Do I then connect them between each other using LORA then connect the drone to one of the bases using NTRIP or NTRIP LOCAL??

Would this even give me a more precise RTK fix over just the 1 base and drone?

How far apart should the 2 RS3’s be from each other for the best results?

For working with a drone, you’d only need 1 RS3. However, if you are planning to do GCP’s etc, you need that second one.

Also note that, unless you setup over known point, like an official monument, you will only have relative precision, not absolute accuracy.


Curious… could you use the drone (with M2?) To collect the control points? I know wouldnt be as convenient as another RS3 on a rover pole… but seems you could using proper offsets and proper plumb laser pointer set down on ground control point?

I guess could be a little awkward… but doable?

1 Like

Naaa, not a precise enough solution.
Rather just take the M2 off the drone then, or better, just buy one more M2.

1 Like


Hi @KN1,

Couldn’t say better than @wizprod. My two cents, though.

If there’s no internet, the Local NTRIP is the single option to establish an RTK link between Reach and the drone.

The less baseline, the better result you get. But it will be a short one in such conditions anyway because the base will be located relatively close to the surveying area.

1 Like

Assuming I won’t have any internet connection. Would I get a more accurate RTK connection if having 2 bases where the main one is getting corrections from the second one while the main one receiving corrections was also connected to the drone to provide RTK.

Also assuming I have an known point for the main base.

Your description sounds somewhat similar to retranslation, but it doesn’t make sense here in terms of accuracy. You’re just adding the excessive chain and thus introducing the error of determining the second base coordinates to the entire dataset. At least, I don’t see how you can benefit from this yet.

I’d place the one base over a known point and send corrections to the drone. If this point is unknown so far, PPP services like NRCan come in handy.

1 Like

This sounds too complicated and if you haven’t done it you may be overthinking.

If you’re doing drone photogrammetry you’re collecting photos with the drone, but you’re also collecting a log of the GNSS signals. The base station is also collecting a log.

RTK means the log data is being sent from the base to the drone, but this isn’t necessary for correcting the positions of photos. You can also take the logs from both and apply the correction later.

You can ALSO correct the location of the base station using a public base station. I don’t know what country you’re in but in America we have CORS. Then you need to set that position as the base position in Emlid Studio or whatever software you use.

Or you can use a known point for the base.

With anything you have to be careful with the coordinate systems. I was doing everything in WGS84 because that’s the coordinate system the drones use but I learned the base station I use in Hawai’i has its position listed in the Rinex file as NAD83 PA11 but the Emlid software doesn’t convert.

In conclusion, don’t overthink but also don’t underthink!

1 Like