ADS-B

ADS-B (Automatic Dependent Surveillance-Broadcast) is a surveillance technology where aircraft determine their position via GNSS and periodically broadcast it, along with identification, altitude, and velocity. Ground stations and other aircraft receive these broadcasts.

• ADS-B Out: Aircraft transmits its position — mandatory in many airspaces worldwide
• ADS-B In: Aircraft receives traffic and weather data from ground stations and other aircraft

ADS-B provides more accurate and frequent position updates than traditional radar, enabling safer separation and more efficient routing. It became mandatory in the US (above 10,000 ft and in Class B/C airspace) in 2020 and in European upper airspace in 2017.