ADS-B

Unlike traditional radars, where a ground-based radar transmits “interrogating” signals and uses the “replies” from aircraft transponders to determine the location, ADS-B equipped aircraft broadcast their GNSS positions through ADS-B message once per second.

The information received by the ADS-B ground station includes the aircraft's identification, altitude, speed, velocity and other useful information.

Unlike multilateration, ADS-B represents dependent information on data from the aircraft's navigation system.

Composite surveillance provides a combination of ADS-B and Wide Area Multilateration in a single deployment to take advantage of both technologies and not depend on data from only the aircraft's navigation system.