PointPerfect SPARTN over NTRIP Distribution
Overview
Introduction
The u-blox PointPerfect service offers GNSS correction data services that enable high-precision positioning. This data is provided in SPARTN format, which is fully supported by u-blox F9 GNSS receiver modules. The SPARTN format is designed to be compact and optimized for bandwidth usage. By using u-blox F9 GNSS receiver modules along with the PointPerfect service, customers can achieve optimal performance. Customers can choose between NTRIP or MQTT as the distribution protocol.
This document specifically describes the NTRIP protocol delivery option. If you wish to use another distribution method such as MQTT or L-Band, please refer to our PointPerfect Service Description page for more information about these options and see other distribution-specific steps in our PointPerfect Getting Started guide.
Benefits of the NTRIP distribution protocol
Accessing PointPerfect corrections data via the NTRIP protocol provides several advantages:
Easy configuration: The widely used NTRIP protocol is supported by many high-accuracy GNSS devices out-of-the-box. Simply configure your NTRIP client with the authentication credentials provided in the Thingstream device management portal at https://portal.thingstream.io/. See more details below.
Improved time to first RTK fix (TTFF): Connecting to the PointPerfect service through the NTRIP protocol provides instant delivery of the first complete set of corrections data to the GNSS receiver, enabling rapid calculation of high-accuracy RTK fixes.
We also provide support for corrections in RTCM format, see the follow page for more information on this: PointPerfect RTCM Distribution (corrections delivered via NTRIP protocol)
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Do's & Don'ts: Best Practices and Common Pitfalls
Do's:
Ensure stable network connectivity: A reliable internet connection is crucial for uninterrupted access to NTRIP correction data. Periodic drops in connection can degrade positioning accuracy.
Select the correct NTRIP mountpoint: Use the appropriate mountpoint for your region (EU, NA, etc.).
Keep your F9 or X20 receiver firmware up to date: Regularly update your receiver firmware to ensure compatibility with SPARTN corrections and to benefit from performance enhancements, bug fixes, and new features.
Verify SPARTN compatibility with your NTRIP client: Not all NTRIP clients support the SPARTN format. Ensure your client is compatible to avoid issues like checksum errors.
Don'ts:
Don't use 3rd party GNSS receivers: SPARTN corrections are optimized for u-blox GNSS receivers like the F9 and X20. For non-u-blox receivers, use RTCM/NTRIP corrections instead.
Don’t exceed geographic boundaries: Ensure your receiver operates within the coverage area of the PointPerfect NTRIP service to avoid receiving corrections outside the intended service range.
Don't share NTRIP credentials: Sharing your login credentials may lead to unauthorized access, disruptions in service, or potential account suspension.
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Still need help?
If you need more help or have any questions, please send an email to services-support@u-blox.com.
NTRIP Architecture and Features
Corrections Data
The PointPerfect NTRIP service delivers PPP-RTK corrections data in SPARTN format, compatible with u-blox F9 GNSS receiver modules. The delivered data includes:
Satellite orbits, biases, and atmospheric corrections every 30 seconds
Satellite clock corrections every 5 seconds
Upon connection, an NTRIP receives a full set of corrections data for quick initiation of RTK fix calculations.
NTRIP versions
PointPerfect supports both NTRIP protocol versions 1.0 and 2.0, automatically identifying the version used by the GNSS receiver device's NTRIP client.
TLS encryption
Secure NTRIP connections using TLS encryption are supported and recommended, provided the GNSS receiver device’s NTRIP client supports TLS.
Here is a diagram describing the communication of SPARTN via NTRIP:
Configuration
Each Thingstream PointPerfect device (‘Thing’) is provided with unique username and password credentials for the NTRIP service. These credentials are exclusive to one simultaneous NTRIP client connection. If a second device attempts to connect using the same credentials, the first device will be disconnected.
Our NTRIP service requires a valid NMEA-GGA (GxGGA) message to be sent regularly to the caster in order to maintain connectivity. If no valid NMEA message is sent within 30 seconds, the connection will be dropped. To prevent a hard disconnect at the 30-second interval, we recommend sending this NMEA-GGA message every 10 seconds. A valid NMEA-GGA message must be within the expected time/location range, contain at least 4 satellites, must be presented in the right format, and the checksum must pass.
Below is the continuation of configuration steps from the PointPerfect Getting Started guide, using the u-center [2] tool to connect the NTRIP stream of corrections to an F9 module.
You should already have:
1. Ensure you have created a PointPerfect Location ‘Thing’ in your Thingstream domain account
2. Retrieve the authentication credentials specific to your device (username and password) from your ‘Thing’
3. Download, install, and open u-center, then connect to the port of your F9 device.
The final steps are to connect your receiver’s client to the NTRIP caster and stream.
Open the Receiver menu in u-center and select the NTRIP Client... as shown in this screenshot.
NTRIP Client Connection Parameters
The service can be accessed with the following configuration:
NTRIP caster address: ppntrip.services.u-blox.com
NTRIP caster ports:
2101 (without TLS encryption)
2102 (with TLS encryption – not currently supported in u-center)
NTRIP mountpoints for different regions or countries:
/EU (Europe)
/US (North America)
/AU (Australia)
/KR (Korea)
Username and Password: <both from your Thingstream PointPerfect device>
The screen shot below shows how to set these values in u-center - the NTRIP client settings screen can be opened via the Receiver tab by selecting: NTRIP Client...
Once you’ve made your selections, click ‘OK.’
After clicking ‘OK’, the NTRIP client will establish a connection with the PointPerfect service and begin receiving augmentation data.
You can check the NTRIP connection status in the u-center's status bar at the bottom of the screen.
Clicking on the green connector icon will open the log, where you can monitor the messages being received.
At this point the F9P is connected to & receiving data from the PointPerfect service, and you can see the performance of the solution via u-center. Please refer to u-center [2] and ZED-F9P documentation [1] for more information on how to analyze the high precision GNSS performance.
Reference Documentation
[1] ZED-F9P Integration manual, UBX-18010802
[2] u-center User guide, UBX-13005250
[3] u-blox F9 HPG 1.32 Interface description, UBX-22008968
[4] C099-F9P application board User guide, UBX- 18063024
[5] EVK-F9P-01 evaluation kit User guide, UBX-22038408
[6] Thingstream Knowledge Base – Services Support
[7] u-blox information on positioning and location technologies - What is NTRIP