A- Demonstration signal
The signal in L1 space is generated and broadcast from a demonstration infrastructure
• The SAGAIE network of GNSS stations, a legacy of the SAGAIE Ionosphere Characterisation project, supplemented by additional stations
A representative prototype system using advanced processing sets and correction algorithms, optimised for African ionospheric conditions
An uplink station deployed in Abuja (Nigeria) and the navigation payload of the GEO NigComSat-1R satellite, using the PRN 147 code.
B- A-SBAS field demonstrations
These demonstrations showed the technical performance of the signal in real configuration and validated the demonstration infrastructure in a global approach. These results confirm the quality of the demonstration signal on L1, and thus the adequacy of the ionospheric models and the effectiveness of the advanced correction algorithms that have been developed.
Beyond the technical validation, these demonstrations also provided an opportunity to promote the benefits of SBAS operations in terms of safety improvement, operational cost reduction and environmental protection. VIPs and pilots from ASKY and Air Côte d'Ivoire, who were on board for the occasion, provided very positive feedback in this regard. A video clip of the demonstrations is available here: https://www.youtube.com/watch?v=UGz4xPxTYaU
Finally, two demonstrations on ancillary services (beyond aviation) were also successfully conducted on July 7 and 8, 2021 in Brazzaville (Congo) with the A-SBAS demonstration signal on L5 providing an open service. The first one concerned the Emergency Warning Service (EWS) by satellite. It demonstrated the system's ability to broadcast an alert message via the A-SBAS demonstration signal to mobile phones, without requiring ground infrastructure. This service transmits an emergency message to the populations concerned, providing information on the type of hazard and the instructions to follow. The second was the transmission of GNSS correction by the A-SBAS demonstration signal to near-market user terminal prototypes for precise positioning applications (PPP).