An aircraft locating system identifies on a TV format radar display the position of a specific aircraft based on an RF transmission from the aircraft on an RF channel. The locating system includes at least a pair of receive stations located within several miles of an airport and separated by a base line...http://www.google.co.uk/patents/US4688046?utm_source=gb-gplus-sharePatent US4688046 - ADF bearing and location for use with ASR and ASDE displays
