RTK and NTRIP setup

Owned by fabian.wolfertstetter
Last updated: Oct 21, 2024 by Christoph Prahl
3 min read

RTK (Real-Time Kinematic) correction is a method used to improve the accuracy of GPS data by using a network of reference stations. Most drones support RTK correction via NTRIP (Networked Transport of RTCM via Internet Protocol), which allows the drone to receive real-time differential corrections over the internet.

RTK Delivery Methods

  1. NTRIP Network Protocol (via GSM Network)

    • Utilizes the Networked Transport of RTCM via Internet Protocol (NTRIP) to disseminate correction signals over GSM networks.

    • Low latency is critical. While the correction signal may be stationary, real-time application is essential to ensure the most current and accurate data is used for corrections.

      • good network coverage in the whole plant is needed

  2. Local Base Station and Rover Setup

    • In this setup, an additional hardware unit, known as the base station, is installed.

    • This base station computes precise positions, but only for its own location. Consequently, the exactness of the drone's position relies on this fixed reference point (==known point).

    • Since the base station’s position is fix, latency in signal transmission is less of a concern.

      • but the connection between drone and base is important

Usage Scenarios

  • NTRIP Use Without Base Station

    • Adequate network coverage is imperative to maintain a reliable connection between the drone and the correction signal across the entire field of operation.

    • The NTRIP base station should ideally be within 100 kilometers to ensure signal integrity.

    • It is necessary to evaluate the NTRIP signal quality directly in the field, as pre-assessment of the network's reliability is not feasible.

  • Base Station Use

    • The base station should be situated at an elevated point, optimally near the center of the solar plant, to ensure a clear line of sight.

    • A continuous, unobstructed network link must be maintained between the base station and the drone for seamless operation.

    • Installation requires the base to be placed under open skies, a safe distance from any metallic structures to avoid interference.

    • The exact geolocation of the base station must be known with great precision, achievable through a process known as a known point setup.

  • Below is a step-by-step guide to set up RTK correction using an NTRIP service provider for DJI drones equipped with an RTK module.

    If there is critically unstable internet at your site, contact Volateq on the details of using Post-Processed Kinematic (PPK) in your case. PPK is a positioning technique that involves post-processing of GNSS data after the data collection is completed. You still need an RTK module on your drone to use it.

Step 1: Choose an NTRIP Service Provider

To get RTK correction data, you’ll need an NTRIP service provider. You can find yours using a google request such as “ntrip service provider *your region*”. Or try these lists to find a suitable service for your region: A portal to NTRIP providers around the world - NTRIP-list https://support.radiodetection.com/hc/en-gb/articles/16203505793309-Europe

Note: some NTRIP providers require a subscription.

Some examples of NTRIP Service Providers:

  1. Trimble RTX – Global coverage

  2. Leica SmartNet – Available in Europe and select regions globally

  3. RTK2Go (by Streambox) – Global service

  4. OmniStar – Global service

  5. Network RTK by local authorities (many countries have their own networks)

Step 2: Obtain NTRIP Caster and Credentials

Once you’ve chosen an NTRIP provider, you will need:

  • NTRIP Caster URL: The address of the NTRIP server.

  • Port Number: The port through which your drone will connect to the NTRIP caster.

  • Mount Point: A reference point within the caster's network that provides correction data.

  • Username and Password: These are provided by the NTRIP service provider when you register for the service.

Make sure you have these details handy.

Step 3: Set Up the RTK Connection on Your DJI Drone

  1. Turn On the Drone and Controller: Power on the drone and the remote controller.

  2. Connect the RTK Module:

  3. Open the DJI Pilot App:

    • On the remote controller, launch the DJI Pilot app.

  4. Go to RTK Settings:

    • In the app, tap the RTK Settings icon, which is typically found in the top-right corner of the main screen.

    • Tap the NTRIP option under RTK settings.

  5. Enter NTRIP Caster Details:

    • Caster URL: Enter the NTRIP Caster URL provided by your service provider.

    • Port Number: Enter the port number.

    • Mount Point: Select or enter the mount point provided by the NTRIP provider.

    • Username and Password: Enter the username and password if required by the service provider.

  6. Enable RTK Correction:

    • After entering all the information, tap on Connect to establish the RTK connection.

    • You should see a status indicator confirming that the drone is receiving RTK corrections when turning green.

Step 4: Start the Mission

Once RTK correction is established, you can proceed with your flight mission. Ensure the RTK signal remains strong throughout the mission to maintain high-accuracy positioning.