MONITOR FOR THE INSTRUMENT-LANDING SYSTEM

摘要

H. Vogel 5-1-1 MONITOR FOR THE INSTRUMENT- LANDING SYSTEM A Monitor located about 100 m from the ILS localizer determines whether the DDM alarm threshold was exceeded due to an equipment error or to an error caused by an overflying aircraft. To accomplish this, either the maximum of the frequency spectrum of the variation with time of the differentiated DDM signal is located, or the frequency spectrum of the variation with time of the DDM signal or of the differentiated DDM signal is compared with one or a plurality of spectra typical of equipment errors or of errors caused by overflying aircraft.