I need an NTRIP licence / How can I check the expiry date/status of the NTRIP licence?

  • Check to see if you have an NTRIP registration form (it will have been sent to you by Fugro Satellite positioning AS or NTRIP).
    To request a new NTRIP registration form, please e-mail marinestar@fugro.com with the following information:
    • IMO number and name of your vessel
    • Fugro serial number for the demodulators (Note! Each demodulator requires its own registration).

NTRIP Overview

NTRIP stands for 'Networked Transport of RTCM via Internet Protocol' and in this context allows users to receive correction data through the internet instead of, or as well as, via Fugro correction satellites. This overview refers to other specific documents for detailed technical information and specifications.

Background

The NTRIP technology is designed to broadcast RTCM GPS corrections using the Internet HTTP standard. In Fugro's receiver the corrections is not necessary only RTCM, they can also be for one of our high precision correction services like G2 (GPS and GLONASS PPP correction service).

The system consists of several smaller subsystems (Source, Server, Caster, Client and User), this document will give a brief description of the subsystems and how they work in theory. Fugro take responsibility of the NTRIP source, caster and server, while the client is the customer/users responsibility. This document should give enough information for the customer/user to prepare to receiver NTRIP corrections data stream(s).

Details

The NTRIP source is the same correction signal that is broadcast to the Fugro correction satellite (note that this is ONLY the correction signal, not subscription activation data). This data which is a combined data stream containing correction for each reference station in the selected area are added to the XP and the G2 data streams. The combination is the final beam/satellite link.

After the adding of HP/XP/G2 signal the data is transmitted to the NTRIP server. This subsystem creates a separate server that converts the combined RTCM and SCF data into a HTTP (Hypertext Transfer Protocol) data stream that is sent to the NTRIP caster.

The NTRIP caster is the broadcasting module of the entire system. The caster broadcasts the data in HTTP format over the internet through a specific port (2101).

This means that any device/client that is HTTP 1.1 compatible can view the framework of the data stream. To access the correction data the NTRIP client must be authorised. This is done with a username combined with a password. This is a case sensitive password that can include letters, numbers and several special characters. If the NTRIP client has correct privileges the data will be received and treated the way the client is configured to.

Equipment

Fugro supplies two pure demodulator units that can receive this NTRIP signal. The first one is the 3610 which can receive corrections through spotbeam and Inmarsat satellites as well as through the internet. For more information about NTRIP on 3610 and how to configure it please see Doc. Ref.: 31150100. The second demodulator is the 3710, similar and same main functions as 3610, but with a more integrated Demodulator-DPS interface.

The other unit Fugro provides that can receive NTRIP data is the 9200-G2/9205-GNSS receiver. This is a combined GNSS receiver and demodulator. This receiver shares some of the same features as the demodulators, but there are some small differences. The biggest difference is that the 9200-G2/9205-GNSS has its own NTRIP signals. For detailed instruction on how to set up NTRIP on the 9200-G2/9205-GNSS please see p. 85 in Doc. Ref.: 31000500 or read Doc. Ref.: 31150102.

All of these units can be configured to use NTRIP as a backup source for corrections or as a main source. In 'main mode' the units will use NTRIP first if the connection is good. If the internet connections drops out they will switch over to use any other means of corrections (e.g. satellite link or external sources).

NTRIP account

To access the content in the NTRIP data stream you must have a user account. This is provided to you by after you have filled out the request form and sent it to FSP support. Keep in mind that this can take up to 48 hours on a standard working day before the NTRIP account is active and ready to be used.

Communication

When NTRIP is configured correctly and is activated the units will constantly receive corrections though internet. This means that for low bandwidth and high cost communication lines (e.g. Iridium) NTRIP is only necessary in combination with Fugro's world-wide GPS and GLONASS orbit & clock corrections service called G2. If the G2 mount point is used the load will be 120 bps while with all other mount points the load is 1200 bps. NTRIP only broadcasts corrections data; this implies that subscription details can only be transmitted through a separate satellite beam. This must be taken into account when planning to include this technology. These data rates are equivalent to 0.07 MB/hour for the 120 bps (G2-only) stream and 0.50 MB/hour for the 1200 bps stream.

Important! NTRIP correction cannot be used as a single reference source. It has to be used as a backup to other method of delivering the corrections signal. The NTRIP corrections goes through an uncontrolled and unknown path to the end user, this makes it unusable as a primary source in mission-critical e.g. DP applications.