CORS & NTRIP - where is this processed

GPS/GNSS Development Boards
1

I have a SparkFun RTK Express Kit on order. One of my first goals is to use this with QFIELD and NTRIP.

I know I will need something like the Lefebure NTRIP Client or SW Maps to receive the NTRIP data because I believe QFIELD cannot receive NTRIP data.

If I use the NTRIP Client or SW Maps to receive the NTRIP data, is the processing of the GNSS data with the NTRIP data done in the RTK Express or in the NTRIP Client / SW Maps app?

I believe I could use NTRIP Client or SW Maps to receive the NTRIP data and connect the app to my RTK Express, then set the ‘mock location app’ on my Android phone to use either the NTRIP Client or SW Maps, and then run QFIELD with the corrected GNSS data (as the Android phone would provide corrected GNSS information to QFIELD).

I am wondering if an alternative would be for the NTRIP Client or SW Maps to receive the NTRIP data and provide it to the RTK Express and also have QFIELD connect to the RTK Express (and receive corrected GNSS information). If this would work, it would eliminate the ‘mock location app’ setting on my Android phone. Because I don’t have the RTK Express yet, I don’t know if it would be possible to connect both the NTRIP Client / SW Maps app and the QFIELD app to the RTK Express at the same time. I would appreciate any insight on this alternate or any other alternate scenario I might want to explore.

2

I’m not sure. QField does not have a NTRIP Client built in (which is surprising), but connects via Bluetooth to the RTK device. That is all pretty straight forward. The difficulty is getting RTCM correction data to the RTK device so that it can get RTK Fix. There are a few ways to do this:

  • RTK Express can connect over WiFi (simultaneously to Bluetooth) to an NTRIP Caster

  • RTK Express can be connected to a serial telemetry radio connected between it (the Rover) and an RTK device in Base mode

  • RTK Facet L-Band can be used (instead of a RTK Express) and obtain corrections from L-Band satellite service and get RTK fix by itself

  • Use a different software other than QField that supports Bluetooth data collection and NTRIP client: SW Maps, Field Genius, SurvPC, etc.

I don’t know of a way to ‘share’ a Bluetooth connection so that you can run Lefebure (for the NTRIP connection) along side QField (for data collection).