ronantaylorware
commented
4 days ago To get RTK in qfield I run the "NTRIP client" app on android. Running the ardusimple F9P with a bluetooth hat on it. Plug gps into phone USBC via OTG cable, in ntrip client app receiver connection is set to External via bluetooth and GPS Mock locations is turned on. Have to turn on mock location in android developer settings. In qfield positioning is then set to internal device. Location access from the top android drop down menu must be turned on. I honestly cant remember which way the data and bluetooth is all going but it works.
Although yes would be nice if QGIS and Qfield had a built in NTRIP client.
Usage is Sparkfun RTK Surveyor (F9P) via Bluetooth from cellphone (Android). Tested with SW Maps and this is working but would like to use QField. The direct Bluetooth connection is recommended by QField documentation but there is no method from QField to send RTK correction data back to receiver over Bluetooth or stream from a public sector data source UNAVCO with RTCM protocol.
Possible workarounds:
Fake GPS instance on Android controlled as listed in QField documentation. The documentation recommends instead a direct Bluetooth connection and avoid this method when possible. As listed the recommended software is not Open Source software and anyways this implements a specific feature of Android so it is not a robust method.
Configure Sparkfun RTK Surveyor to connect to WiFi hotspot and integrated RTCM / NTRIP client, then connecting from QField to the Sparkfun RTK Surveyor using Bluetooth as recommended. This works only when there is a full size AP with a good antenna close by the RTK Surveyor unit. This method is not reliable using cellphone built-in hotspot, the signal is weak to the device and besides this the cellular carrier assesses phone hotspot Internet sharing differently than data used from apps within the phone device so there are carrier-level complications.
Running own base station for corrections data and a serial data link over RF. Extra cost, setup, and not convenient where there is a source of NTRIP / RTCM data valid for the area being surveyed.
I searched the discussions and forum finding some references to F9P hardware, and even the Sparkfun Facet, but nothing sure about how to use QField with a direct Bluetooth connection as recommended and also streaming correction data that is sent over that Bluetooth link back to the RTK Surveyor; as SW Maps is doing successfully.
Suggestion is an enhancement: Add an NTRIP client to QField and support bi-directional communication of this RTK correction data with the Bluetooth connected receiver.