Adf bearing and location for use with asr and asde displays

Abstract

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 which is in near proximity to at least one runway at the airport or a theoretical extension thereof. Each receive station includes a passive receiver for determining a bearing angle to a source of RF on the RF channel for generating a signal representative of the bearing angle. The locating system further includes a processor which is responsive to bearing angle signals derived from the receive stations for generating line count and line delay information. The line count and line delay information correlate a position determined by the bearing angle signals from at least a pair of receive stations with a frame of reference of the TV display. The system further includes a video mixer which responds to two different input signals. A first input signal to the video mixer is a scan converted radar return signal. The second input signal to the video mixer is the line count and line delay information. The output of the video mixer is used to drive a video display. The video display, subjected to the two identified inputs can highlight a location identified by the line count and line delay information so that for example a person viewing the display would be able to identify which of perhaps plural radar returns shown on the display is associated with an aircraft which is actively transmitting on the RF channel.