DIGITAL RANGE COMPUTER SYSTEMS FOR AIR NAVIGATION SYSTEMS SUCH AS TACAN

摘要

A digital range computer which may be incorporated in a Tacan air navigation set is described. The computer includes a calculation unit which calculates the range from information as to the elapsed time between interrogation and reply signals. The signals are inputed to the calculation unit via the input control and range gate control unit. Another control unit is operated by the calculation unit and generates synthetic reply signals on the basis of the calculations previously made. The synthetic reply signals are used in the control unit so as to maintain the calculation unit operational on a continual basis, notwithstanding the absence of reply signals. The synthetic reply signals are also utilized by an acquisition control unit in order to condition the system, either in a search or tracking mode of operation.