simpleRTK2B connection to a NTRIP correction service

We have shown some figures about the performance of the ZED-F9P in the simpleRTK2B shield in base-rover configuration, where the base sends corrections to improve the accuracy of the rover position.
The base-rover configuration has some advantages:

  • No external infrastructure required
  • No need for cellular network coverage

But also has some limitations:

  • The range of RTK corrections is limited to ~20km from the base
  • The range of RTK corrections is limited also by the radio link between the base and the rover which, in some cases, must have direct line of sight

When these limitations are a problem, simpleRTK2B can be used as a standalone board and RTK corrections can be fed to it via an external NTRIP service.
In this post we will show how easy it is to connect your shield to a NTRIP caster.

What hardware do you need for this configuration? We came out with 3 different options but with the shield flexibility you can think of others!

1) simpleRTK2B + computer with internet connection
2) simpleRTK2B + Bluetooth module + smartphone with internet connection
3) simpleRTK2B + Xbee Cellular 3G radio (3G network required)

The last option needs some programming so we will focus on the other two options.

Before starting the tutorial, you need to find a NTRIP service provider that covers your geographic location.
If you are not aware of them, check this list: https://igs.bkg.bund.de/root_ftp/NTRIP/streams/streamlist_world-wide.htm
Most of these services are free but require registration.

In this tutorial we will use two services:

  1. CatNet GNSS network from the Institut Cartogràfic i Geològic de Catalunya
  2. ERGNSS network from the Instituto Geográfico Nacional

Both services are free and have coverage in the area where the tests take place.

1) simpleRTK2B + computer with internet connection

  • Connect your computer to the simpleRTK2B board with a USB cable.
    You can also use a Bluetooth connection.
  • Open u-center and connect to the proper COM port
    u-center COM connection
  • Go to Receiver > NTRIP Client… and enter the settings of your NTRIP caster
    NTRIP caster
  • Click the Update source table button, wait a few seconds for u-center to retrieve the information and click the Mount point details button.
    In the window you will see details of the different stations that belong to your NTRIP service provider.
    Some of them broadcast generic information while others use your position to send you custom corrections.
    NTRIP mount points
  • Select your preferred NTRIP mount point from the drop down list and click OK
    NTRIP settings
  • And that’s all! You can check that everything is working if you see the green icon in the NTRIP client section at the bottom of the u-center screen.
    NTRIP ok
  • In a few seconds you should also see in the u-center information panel that Fix Mode has changed to 3D/DGNSS/…
    ucenter RTK info

2) simpleRTK2B + Bluetooth module + smartphone with internet connection

  • Enable Bluetooth on your smartphone
  • Download and open the Lefebure NTRIP Client application
    NTRIP smartphone step 1
  • Click on the gear icon to enter the setup menu
    NTRIP smartphone step 2
  • Select Receiver Settings and set:
    Receiver Connection to External via Bluetooth
    Bluetooth Device to the name of the simpleRTK2B BT connection
    You can additionally log the GPS or NTRIP Data by checking the options.
    NTRIP smartphone step 3
  • Go back to the main settings menu and select NTRIP settings.
    Set your NTRIP service credentials (Caster IP, Caster Port, Username and Password).
    NTRIP smartphone step 4
  • Go to the main screen and click the CONNECT button.
    Once the connection with the server is stablished, the app will ask you to select the NTRIP station from which you want to receive the corrections.
    NTRIP smartphone step 5
  • And that’s all!
    The application will show information of the simpleRTK2B status, which can be configured in the Display Settings menu.
    If you want to see more information, you can connect (in parallel) the simpleRTK2B board to a computer (no internet is required) via USB cable and run u-center as usual.
    NTRIP smartphone step 6

In the next post we will show the performance of the simpleRTK2B shield in standalone configuration with NTRIP corrections.