A new Interface Control Document (OS SIS ICD v2.0) has been issued by the EU Agency for the Space Programme (EUSPA) in January 2021, introducing major updates to Galileo Open Service signals. In particular, three changes for the I/NAV message transmitted on the Galileo E1-B signal component.
Although these modified signals are not yet being broadcast by the Galileo satellites, this document allows receiver manufacturers to prepare for the implementation of the new I/NAV capabilities now.
Three new features in the I/NAV message transmitted on the Galileo E1-B signal component:
- Reduced Clock and Ephemeris Data (RedCED);
- Reed-Solomon Outer Forward Error Correction Data (FEC2); and
- Secondary Synchronization Pattern (SSP).
These new features represent a major evolution of the Galileo Open Service signals, which will provide all users with a more robust and faster retrieval of the Clock and Ephemeris Data, particularly for users in challenging environments, while at the same time allowing for a faster reconstruction of the Galileo System Time (GST). This will result in a faster Time to First Fix for users whose receivers are able to exploit the new solutions.
Manufacturers and developers can now use SatGen to test receivers in preparation for the transmission of the new Galileo I/NAV messages. Reduced Clock and Ephemeris Data (RedCED) and Secondary Synchronization Pattern (SSP) have already been implemented. Reed-Solomon Outer Forward Error Correction Data (FEC2) will follow in the next SatGen release.
The Galileo system is set to begin transmitting the new I/NAV capabilities by 2023.
