Which system does ADS-B require for providing position data?

Automatic Dependent Surveillance–Broadcast (ADS-B) relies on satellite signals for providing accurate and up-to-date position data. The system works by equipping aircraft with a GPS receiver that calculates the aircraft's precise position, which is then broadcast automatically to ground stations and other aircraft. This position data is crucial for air traffic management, enhancing situational awareness for both pilots and air traffic controllers.

Satellite signals provide the necessary accuracy and reliability that ADS-B requires to function effectively at all altitudes and in various environments, enabling improved tracking of aircraft in real time. Other systems, such as ground-based radar or automatic flight control systems, do not provide this type of positioning data in the same manner as satellite signals, nor do local weather observation data play a role in the determination of an aircraft's position in the context of ADS-B. The dependence on satellites is what distinctively characterizes the system's operation and functionality.