The Satellite-Based augmentation System (SBAS) integrity concept requires the system to alert users of “out of tolerance conditions” within a required delay compatible with intended operations.

The study aims to reduce the system time to alert on SBAS, with the aim of maintaining simplicity despite an increase in complexity.

The study also notes that the European Geostationary Navigation overlay Service (EGNOS) currently complies with the 6-second time to alert requirement compatible with Category I precision approach operations.