For future aeronautical navigation, ICAO recommends the further development of Global Navigation Satellite System (GNSS) based technologies as primary means for navigation. However, the drawback of GNSS is its inherent single point of failure – the satellite. Due to the large separation between navigational satellites and aircraft, the received power of GNSS signals on the ground is very low. As a result, GNSS disruptions might occasionally occur due to unintentional interference, or even intentional jamming. Yet the navigation services must be available with sufficient performance for all phases of flight. Therefore, during GNSS outages, or blockages, an alternative solution is needed. This is commonly referred to as Alternative Positioning, Navigation, and Timing (APNT).
One of such APNT solution consists of integrating the navigation functionality into LDACS, referred to as LDACS-NAV. The ground infrastructure for APNT is deployed through the implementation of LDACS ground stations.