GPS Applications in Transportation and Logistics

Civil aviation adopted satellite navigation extensively once GPS accuracy improved after 2000, transitioning from ground-based radio beacons such as VOR (VHF omnidirectional range) and NDB (non-directional beacon) toward satellite-based Area Navigation (RNAV) and the more stringent Required Navigation Performance (RNP) standards, which specify a required positioning accuracy the aircraft's navigation system must maintain and monitor in real time, such as RNP 0.3 requiring the aircraft to stay within 0.3 nautical miles of its intended path 95 percent of the time. The U.S. Federal Aviation Administration's Wide Area Augmentation System (WAAS), operational since 2003, and its European counterpart EGNOS broadcast correction signals from geostationary satellites that improve GPS accuracy to within a few meters, enabling GPS-guided precision approaches to runways that previously required expensive ground-based Instrument Landing System (ILS) infrastructure. Aircraft also broadcast GPS-derived position via Automatic Dependent Surveillance–Broadcast (ADS-B), a system the FAA mandated for most U.S. airspace beginning January 1, 2020, allowing air traffic controllers and nearby aircraft to track position more precisely than legacy radar.