Post-processing RTK data using corrected base-station position

Emlid Studio Static / Kinematic processing
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Hi all,
I am working on a project conducting a drone-based SfM survey; we used RS2’s (a base and 2 rovers) to establish the GCPs. We did not have a known benchmark to locate the base station over, so did an “average single” point set up (30 mins) to get an approximate position. We then collected our GCPs running RTK with the base.

However, in the hopes of eventually refining our actual locations after we returned from the field, we ran the base for 4 hrs the next day to collect enough data for a PPP refined location. We have since submitted our PPP data to AUSPOS and CSRS to establish the actual base station location.

My question is: it’s not clear to me how to reprocess the original rover observation files in Emlid Studio using the corrected base station location. I ran the kinematic processing routine using the original rover file, uploaded the base file and provided the updated position (LLH) from the PPP results (rather than using the Rinex Header Position, which was the original “average single” position), then the navigation file for the rover. This sequence appears to have recalculated the ground track recorded during the survey, but not the actual GCP sites (which we collected as distinct 30-second points).

I also tried the Stop&Go routine (following the same steps above for the Processing step) but after doing the “Generating corrected CSV step, the resulting file only produced one recalculated location (the first location); the rest have errors for the LLH values (”#NAME?"), and even that one still lists the base station location as the original (non-corrected) location.

Anyone have a solution on this?

thanks

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Hi @dhclark,

Welcome to our community!

As I see, you’re post-processing logs from your rover and base using accurate base coordinates. Do you have questions about the workflow or face any difficulties?

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Hi Kseniia, I just finished my post. Got called away yesterday.

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Does anyone have thoughts on my concerns here?

thanks

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Hi @dhclark,

Sorry for the silence here!

it’s not clear to me how to reprocess the original rover observation files in Emlid Studio using the corrected base station location

You are right – it should be possible to do it in the Stop&Go mode. As I see, you have all the required data: the raw data from the base and rover, the CSV file with the points from Emlid Flow, and the corrected base position.

If this workflow gives you errors, I’ll need to look into the data to check what’s wrong. Can you please share the dataset and the accurate base coordinates with me? If you’d like to share the data privately, you can send it to support@emlid.com.

In the meantime, you can also correct the data by applying the shift in software like Excel:

  • Calculate the difference between the base position used in RTK and the accurate position

  • Add this shift to all the rover coordinates from RTK

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