GBAS (Ground-Based Augmentation System) is a system designed to improve the accuracy, integrity, and reliability of GNSS signals, particularly for aviation applications. It provides real-time corrections to GNSS data (such as GPS) to enhance the precision of navigation and position determination.
GBAS works by using a network of ground-based reference stations that receive GNSS signals, calculate corrections, and then broadcast these corrections to aircraft or other users in the vicinity via a local data link. This allows for more precise navigation, especially in critical phases of flight like approach and landing.
The key components of a GBAS are:
- Reference Stations: These are located at known positions and receive satellite signals to compute correction data.
- Data Link: The corrected data is transmitted from the reference stations to aircraft in real time.
- Aircraft Receiver: Receives the corrected signals from the ground station to improve the GNSS positioning accuracy.
GBAS is typically used in airports and airspace where high-precision navigation is essential, such as in instrument landing systems (ILS) or precision approach procedures. It is seen as a potential replacement or enhancement for traditional ground-based navigation aids, offering increased flexibility and coverage.
