Local area augmentation of GPS for the precision approach of aircraft

摘要: The Federal Aviation Administration (FAA) is investigating the feasibility of using Global Positioning System (GPS), together with local augmentation as primary navigation system for Category II and III precision approach aircraft. This augmented would be known a area (LAAS) because it place subsystems on ground at or near an airport to greatly enhance performance airborne GPS receivers approaching that airport. LAAS complement space-based augmentations GPS, such wide system. When complete, integrated will meet stringent requirements accuracy, integrity, continuity, availability. Indeed, improve accuracy from approximately 100 m stand-alone better than 1 m. high required so can guarantee integrity continuity aircraft guidance during phase flight. Integrity requires detect any situations which threaten safety landing, notify within 2 s threat. Continuity competing consideration-it total number alarms, true plus false, sent very small. High guarantees aborted approaches manageably Finally, availability fraction time operational-providing position fixes specified continuity. paper describes has been proposed by FAA. It discusses fundamental operation LAAS.