GBAS NSE model for CAT II/III autoland simulations

Since many years, civil aviation has identified GNSS as an attractive mean to provide navigation services for every phase of flight due to its wide coverage area. However, GPS standalone cannot meet ICAO requirements in terms of accuracy, integrity, availability and continuity, particularly in the case of precision approaches. To achieve improved level of performance, different augmentation systems have been developed aiming at enhancing and monitoring the quality of the Signal-In-Space (SIS). In particular GBAS, for Ground Based Augmentation System, allows guarantying a very high level of performance in a given coverage area surrounding an airport for example.