Air space monitoring - and connecting piece radar

摘要

A radar system (10) which time shares the use of a common radar head (12) to perform functions associated with Air Surveillance Radar (ASR) and Precision Approach Radar (PAR) systems, i.e., for respectively displaying information to an air traffic controller useful for tracking an aircraft's approach to an airport and then guiding said aircraft along a preferred glideslope approach to a runway. In accordance with a significant feature of a preferred embodiment, a common radar head (12) is comprised of an azimuth antenna (14) capable of using radar beams to scan, e.g., electronically, a subsidiary scan arc, i.e., less than + 90 degrees, mounted on a rotational scan apparatus that directs said radar beams within a principal scan arc, a full circle (360 degrees), by continuously rotating, e.g., mechanically, said azimuth antenna (14) at an essentially constant rate. By periodically advancing, preferably electronically, the emission direction of the rotating azimuth antenna (14), time periods are allocated that can be used to individually permit both ASR and PAR emissions to occur at one or more common rotational positions.