Export GPS Data for Post-Processing

[SaraJL]

Has anyone used ArcGIS Field Maps to do high-accuracy data collection with a receiver? It sounds like the information for post-processing GPS data is collected but not supported in the app itself.

I'm just curious if anyone has a workflow they would recommend if they have been using Field Maps with a GNSS receiver. Any thoughts?

Thank you!

[Anonymous User]

Can you elaborate on your question regarding post-processing GPS data? In the link you posted it takes you through all the steps to pair a GNSS receiver and if you Prepare your data to record GPS metadata
you'll have the GPS data contained in those fields. 
 
Then you use whatever software you use to post-process if you need that level of accuracy.

[SaraJL]

Thank you for the reply! I'm looking specifically at the Differential Corrections section of the article - it mentions that Field Maps stores the information for post-processing but does not directly support it. I'm trying to figure out exactly what type of data or files Field Maps is storing for post-processing (for example, some GPS software stores an RINEX file). 

I suspect I would have to use another software like GPS Pathfinder or RTKLib, but I think that software looks for specific files beyond just the shapefiles or geodatabase. This GIS Stack Exchange post is probably similar to what I need to do. 

Thank you again!

[SaraJL]

I chatted with ESRI on this and got an answer! In general, when ESRI in the article refers to post-processing, they are referring to traditional geoprocessing.

Field Maps only stores shapefiles, geodatabases, feature services, etc - but not the information that would be usually needed to post-process GPS data after collection in the field. So unfortunately - GPS data gathered with Field Maps can't be post-processed into some else (like GPS Pathfinder, for example). 

[kterry1983]

Hi Sarah,

Did you ever find a way to post-process Field Maps data? Or did you resort to switching back and forth between two apps? If so, which app do you use for the data that will be post-processed? 

[DougMorgenthaler]

@SaraJL many GPS receivers support capturing session logs, such that if capture those as well you'd have the necessary information to post-process when combined with the point features with GPS metadata.  Note, currently there aren't any facilities for capturing this metadata on lines or polygon features.

[EKulack]

My organization is very interested in a streamlined GNSS differential correction post-processing solution to the Field Maps workflow. Currently it doesn't seem like there is one. It is a significant weakness to the Field Maps offline workflow when requiring mapping or survey grade accuracy and at this point requires us to use Trimble or Leica workflows complicating data collection for our users. 

[kterry1983]

I work for a government natural resources dept. and have the same issue. If a conversion exists, it would be nice to know. 

[SaraJL]

The main issue is that GPS session logs are not typically in a format that is compatible with differential correction (post-processing). Typically we need .cor files - which we can plug into Pathfinder Office or other post-processing software to get the correct output. But even if you have the .cor files, Field Maps or ArcGIS Pro doesn't have a way to perform the differential correction process.

If you want to see a general example process, here is what we do now in Pathfinder Office: Export Data from Pathfinder Office

I just want to reiterate, that we don't want to duplicate Pathfinder Office by any means, but we just need the correct file types to do the differential correction. We also want to try to do most of this process in ESRI software - having to use multiple different types of software to do one project is not ideal.

[SaraJL]

I might have a couple of updates for this thread in case anyone was still following!

So a little background - the process we used to use post-process data would need to be done in Pathfinder Office because we had ancient Trimble units. We now have some newer ones (we use TDC600s with an R2 antenna for sub-decimeter accuracy). The challenge with this is that unless you want to sign on for Frontier's Trimble Catalyst or some other kind of software (don't remember the name at the moment) you can no longer do post-processing.

Per the rep I spoke to, they do say that at sub-decimeter it's accurate enough to not need post-processing (that is what they said). Which put us in a bit of a bind because with strict budgets we don't purchase subscriptions unless it's critical. 

Long story short - we still don't have a resolution for it. If post-processing is required for a particular analysis, we use the old ancient units and do the post-processing in Pathfinder Office.

If anyone else has any new developments, I'm curious to hear it!

I hope everyone is doing well!