GBAS uses monitoring stations at the airport to process signals from
core constellations (currently GPS L1) and broadcasts corrections and
approach path data to support precision approach operations. SBAS uses a
wide network of ground stations and provides signals from Geostationary
Earth Orbit (GEO) satellites to support operations over a large
geographic area, from en-route down to approaches. Expected benefits
from GBAS/SBAS implementation involve the enhancement of safety through
the geometric vertical guidance for final approach and improvement of
accessibility to regional airports in addition to the general benefits
gained from PBN implementation, i.e. improvement of operational
efficiency, increase of airspace capacity, reduction of noise and CO2
emission.
Necessity of Argumentation System:
The navigation system should meet four requirements.
Accuracy: accuracy in the means of position information. Is the position is correct?
Integrity: ability when the navigation system occur error and the ability to inform the situation within the certain time. Is the information right?
Continuity: ability to provide the navigation service continually. Does the service continue? What is the availability ratio?
Availability: ability to have the accuracy, integrity and continuity. Is the availability ratio high?
