ADS-B
Automatic Dependent Surveillance-Broadcast (ADS-B), and specifically space ADS-B, is a precise space surveillance system that uses GPS to determine airspeed, location, and other information about aircraft.
Signals emitted from ADS-B transponders on aircraft are captured by receivers in space and then broadcasted to a network of ground stations. ADS-B offers lower infrastructure costs and improved situational awareness compared to traditional radar and radio systems.