Differential corrections on OxTS units- Internal NTRIP Client

• NTRIP overview
• Introduction to Internal NTRIP
• Using an NTRIP service
• Method
• Monitor NTRIP status
• Mount point configuration troubleshooting

  • Issue - Mount point table displaying as empty

  • Issue - Not retrieving Mount point table

NTRIP overview

NTRIP (Network Transport of RTCM via Internet Protocol) is a form of RTK differential correction that transmitted using the TCP/IP protocol (e.g. Ethernet / WiFi networks)

This means that instead of using the traditional base station and radio to send correction data to a rover, data is sent using the internet to a cellular modem with a data plan. The NTRIP corrections can then enable you to reach RTK accuracies where using a base station is not feasible

Introduction to Internal NTRIP

Rather than using an external device, Internal NTRIP uses software on the unit itself to receive corrections. For this a direct Internet connection is required (wired or Wi-Fi) to the NTRIP caster. Internal NTRIP is Feature Code protected and needs to be enabled to unlock this capability, this is available on all xbns based units.

Using a NTRIP service

Some service providers require you to log in to their service to collect mounting point information. And some of them are password protected and will require you to have an account with them.

If you are connecting to an NTRIP service that is protected, you will have to access the list of mounting points yourself.  The Mount Point can then be added manually to the RT. For help with this, please get in contact with our support team. 

It is important to note, that some NTRIP subscriptions require the unit to be initialised before corrections are sent.

Method

In order to get corrections to the internal client, 5 pieces of information are needed:

• Host address (domain name or IP of caster)
• Port (default is set to 2101)
• Mount point (Which system you are connected to)
• Username
• Password
• Network Gateway

The network gateway is set to 192.168.25.1 as default, but ensure this is changed if this isn’t the network gateway. It is best practice to have the unit and the gateway on the same range, if this isn’t the case the IP of the unit can be changed in NAVdisplay with the following command:

‘!CONFIG IP xxx.xxx.xxx.xxx’   

where xxx.xxx.xxx.xxx is the IP address the unit will be change to e.g. ‘195.0.0.10’

Further information can be found in the useful guides, but this article will show the basics of a configuration.

• Select both ‘Enable NTRIP’ and ‘Use internal NTRIP client’, then fill in information required.
• Configuring internal NTRIP is done in the same way for all units including the AV200 and xNAV650.

Monitor NTRIP status

After the method above has been followed, connect the INS via Ethernet to the device providing the internet connection and the INS will be configured and ready to go. The NTRIP status can be monitored in NAVdisplay:

• Go to Widgets > Digital.
• Search 'ntrip' in the search bar.
• Select the 'NTRIP status' message (will be the only result).

Here is a list of the possible values that the NTRIP status message can give and what they mean:

"NtripClientState", "NTRIP Client State"
"Invalid", "Invalid"
"Ready", "Ready to connect"
"ResolveUrl", "Resolving URL for ip"
"GetSourceTable", "Getting source table"
"ParseSourceTable", "Parsing source table"
"Authentication", "Providing authentication"
"Running", "Running"
"Close", "Triggering closing of connection"
"Closing", "Closing connection before retrying"
"Reconnecting", "Reconfiguring and reconnecting"
"Disabled", "Disabled"
"ErrUndefined", "Error, undefined"
"ErrBadAuth", "Error, bad authentication"
"ErrTcpFailed", "Error, TCP connection failed"
"ErrBadMountPoint", "Error, unrecognised mount point"
"ErrResolveUrl", "Error, unable to resolve URL"
"ErrAddress", "Error, invalid address string"
"ErrPort", "Error, invalid port number"
"Unknown", "Unknown NTRIP State"

Mount point configuration troubleshooting

Issue - Mount point table displaying as empty

Cause - Secure NTRIP host domain. If your NTRIP correction host is a password protected domain, then the Mount point selection table will display as empty. See following example:

Solution

Carry out the following setup steps:

1. Go to your NTRIP providers website and login into your account.
2. Locate Mount point table and pick the mount point you wish to use.
3. Copy the mount point name.
4. Connect to unit via Ethernet on a network WITHOUT internet access and open NAVconfig.
5. Configure unit and progress to internal NTRIP client.
6. With no internet connection the Mount point input box should allow text input. Paste your previously copied mount name here.
7. Enter username and password for mount point and proceed with configuration.
8. Enable WiFi interface on unit. Click here for detailed instructions on this process.
9. Commit configuration to unit.
10. Turn on your desired mobile phone hotspot.
11. Enter units WiFi configuration tab.
12. Modify units WiFi configuration by dragging hotspot network into connection list.
13. Commit configuration to unit.
14. Enjoy mobile NTRIP corrections!

Issue - Not retrieving Mount point table. See following pic.

Cause - Invalid host domain. If your host domain is not password protected, then it is likely your host address is invalid.

Further help - Mobile NTRIP connection check list

If you have carried out the above steps correctly and are still not receiving NTRIP corrections you can check the following things:

  WiFi is connected -it may take a few minutes for the WiFi to initialise and connect to your phone. Connection status can be monitored in your phones connection manager.

  Mobile network is connected -check your mobile phone has signal and is able to connect to the internet.

  Configuration is correct -check the configuration of your internal NTRIP client in NAVconfig making sure all information input is correct.

  Contact OxTS Support -if you have carried out all the above instructions and are still not receiving differential corrections, then please contact OxTS Support for further assistance.