The improvement of positioning accurary using ground-based augment system (GBAS) requires various error correction values via the ground-based VHF digital broadcast. This paper proposes a tropospheric index correction algorithm that distinguishes the wet and dry proportions of the atmosphere through analyzing the conventional tropospheric error correction algorithms. The sampling and calculation validated that this algorithm significantly improved the accuracy of tropospheric error correction. The advantages of GNSS landing system (GLS) are discussed, as well as the flight procedure design and operational methods for GLS approach, giving suggestions to accelerate the application of GBAS in China.

ground-based augment system  /  GNSS landing system  /  VHF digital broadcast  /  FAS data block