Tracking of aircraft groups in an operational Air Surveillance System

An operational Air Surveillance System shall generate a stable and reliable air picture. In dense target situations the quality of available sensor data is reduced. System models which take into account correlated flight paths of aircraft formations help to compensate the lack of information in dense situations. The aim is to improve the tracking capabilities in dense situations and to continue the tracking of group members as individual aircrafts. The paper describes algorithms to detect groups, to evaluate the relative behavior of group members and to handle group maneuvers like split and join events. As a summary a robust algorithm of group tracking is presented which is in operational use in the German Air Defense System GIADS.