PointPerfect RTCM Distribution
Overview
Introduction
The u-blox PointPerfect service offers GNSS correction data services that enable high-precision positioning. This data is provided in either SPARTN or RTCM data formats.
This document describes only how to receive PointPerfect corrections in an RTCM data format using the NTRIP protocol. More information about SPARTN data via NTRIP or other delivery options can be found in the PointPerfect Service Description page or the PointPerfect Getting Started guide.
We also provide a SPARTN/NTRIP corrections service, information about this service is available on the following page: PointPerfect NTRIP Distribution
RTCM data format
The RTCM data format applies a standard for the network communication and encoding of GNSS data. It was the first published standard by the Radio Technical Commission for Maritime Services for Differential GNSS and is used today by many high-precision GNSS receivers.
PointPerfect delivers RTCM 3.3 via NTRIP when a user selects an RTCM plan.
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 RTCM via NTRIP:
Still need help?
If you need more help or have any questions, please send an email to services-support@u-blox.com.
Configuration
Each Thingstream PointPerfect device (‘Thing’) is provided with unique username and password credentials for the RTCM/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.
Early adopters will be given unique credentials for each device (or Thing) on their domain that has selected a PointPerfect RTCM plan.
Prerequisites for using the RTCM service
The ability to create a PointPerfect Location ‘Thing’ should be enabled on your Thingstream domain when this page was shared with you. If you find any of the steps below are not available to you, please send us a message.
IMPORTANT: User credentials for each Location ‘Thing’ include a 36-character username, but some NTRIP clients require a shorter length username. Please check the username requirements of your NTRIP client before creating your RTCM device on your domain. If your NTRIP client cannot accept our current username length, submit a request with your Thingstream domain name and the desired length of your username credentials. This length can be between 6-20 characters, and we recommend for security purposes using the maximum length allowed by your client.
Create a new RTCM Thing
On your domain, go to Location Services > Thing List > Add Location Thing. Select the PointPerfect tab and choose “Add a PointPerfect Thing”
You will be prompted to enter a friendly Thing name, and to select the Format of data corrections provided for this device. Choose RTCM: Correction data for use with any other receiver
IMPORTANT NOTE: This option cannot be changed in your device after it is created. If you wish to use the SPARTN format you must create a new PointPerfect Thing.
Choose the plan you wish to apply. Early adopters will have access to our RTCM Trial option.
Configure your NTRIP Client
Each Thingstream PointPerfect device (‘Thing’) is provided with unique username and password credentials for the RTCM/NTRIP service. You will find these credentials under the Credentials tab of your Thing Details.
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.
NTRIP Client Connection Parameters
The service can be accessed with the following configuration:
NTRIP mountpoint: NEAR-RTCM <update source table if not seen>
Username and Password: <both from your PointPerfect Thing credentials>
NOTE: If your NTRIP client does not accept the length of the username, please send a request specifying the username length required and we will update your domain. New devices created after this adjustment will apply your new username length. Simply deactivate any Thing that you will not use to stop any billings from it.
EndPoint Address:
this address is region specific
Port: two options available
2101 (without TLS encryption)
2102 (with TLS encryption – not currently supported in u-center)
The screen shots below show how to set these values using our u-blox GNSS receiver tool u-center and a u-blox F9 receiver. 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] for more information on how to analyze the high precision GNSS performance.
RTCM messages
The following is the list of RTCM messages that are provided:
1005 --> station description
1032 --> physical reference station position
1033 --> receiver and antenna description
MSM4
1074 (GPS)
1094 (GAL)
1124 (BDS)
Do's & Don'ts: Best Practices and Common Pitfalls
Do's:
Send GGA messages every 10 seconds: The NTRIP server needs a current GGA message from the rover to ensure correct localized corrections. Most NTRIP Clients are set to send GGA every 10 seconds. (The NTRIP server disconnects if no GGA is sent within 30 seconds.)
Verify your NTRIP credentials: Double-check that your endpoint, mount point, and credentials (username, password) match with what is within your Thingstream portal.
Keep your NTRIP Client up to date: Outdated NTRIP Clients can face connection issues with the NTRIP Server.
Don'ts:
Don’t use SPARTN for 3rd party receivers: Only u-blox receivers, such as the F9 or X20 series, can benefit from SPARTN over NTRIP. Third-party receivers are not compatible with the SPARTN format and will need to use RTCM over NTRIP distribution.
Don’t send inaccurate GGA messages: Some NTRIP Clients send fixed or “baked” GGA messages that don’t reflect the rover’s real-time position. This can lead to DGNSS or Float problems. Always ensure GGA messages reflect the rover’s current location.
Don't share NTRIP credentials: Sharing your login credentials may lead to unauthorized access, disruptions in service, or potential account suspension.
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