The International Civil Aviation Organisation (ICAO) is currently working on the next iteration of Ground Based Augmentation System (GBAS) enabling CAT II/III approaches, GBAS Approach Service Type (GAST) E, supporting Dual Frequency Multi-Constellation (DFMC) GBAS. This concept will make GBAS more resilient to ionospheric activity and radio frequency interference (RFI), improve overall performance, and it will include use of Galileo and BDS constellations.
Work on the DFMC GBAS Standards and Recommended Practices (SARPs) is ongoing, and the standard is not sufficiently mature to design ground subsystems. This project will continue the evolution of DFMC GBAS, contributing to the standards and their validation, focusing on integrity and continuity allocation and mitigation of the satellite fault integrity threats. It is crucial to show that threat mitigation can be achieved for the DFMC GBAS concept being standardised.