The problems of the present management information system are introduced. A solution based on field-bus is proposed to overcome the problem. A issue how the old instruments is applied to the new system is discussed, a...The problems of the present management information system are introduced. A solution based on field-bus is proposed to overcome the problem. A issue how the old instruments is applied to the new system is discussed, and a rebuild method of the old instruments with LED or LCD to fit the solution is provided.展开更多
From the actual perspective of working principle of localizer beacon subsystem of Instrument Landing System (ILS), consideration of the distance information from localizer antenna to field monitor antenna and wide ape...From the actual perspective of working principle of localizer beacon subsystem of Instrument Landing System (ILS), consideration of the distance information from localizer antenna to field monitor antenna and wide aperture effect of localizer antenna, broke through the limitation of signals synthesized only far-field (FF), established the near-field (NF) model. The three-dimensional mathematical model of localizer beacon was designed, and the signals at both near-field and far-field were analyzed qualitatively. At the environment of Antenna Fault as well as Antenna Distribution Unit (ADU) phase shifter simulation, the characteristics of near-field and far-field were also compared. The simulation results showed that the model met the requirement of theory of localizer beacon, and the gap between two models was so evident, which resulted from the broken geometric symmetry in NF area. The model could provide valuable theoretical basis for performance evaluation and maintenance of the ILS, and meanwhile, provide reference for the further analysis of localizer beacon.展开更多
文摘The problems of the present management information system are introduced. A solution based on field-bus is proposed to overcome the problem. A issue how the old instruments is applied to the new system is discussed, and a rebuild method of the old instruments with LED or LCD to fit the solution is provided.
文摘From the actual perspective of working principle of localizer beacon subsystem of Instrument Landing System (ILS), consideration of the distance information from localizer antenna to field monitor antenna and wide aperture effect of localizer antenna, broke through the limitation of signals synthesized only far-field (FF), established the near-field (NF) model. The three-dimensional mathematical model of localizer beacon was designed, and the signals at both near-field and far-field were analyzed qualitatively. At the environment of Antenna Fault as well as Antenna Distribution Unit (ADU) phase shifter simulation, the characteristics of near-field and far-field were also compared. The simulation results showed that the model met the requirement of theory of localizer beacon, and the gap between two models was so evident, which resulted from the broken geometric symmetry in NF area. The model could provide valuable theoretical basis for performance evaluation and maintenance of the ILS, and meanwhile, provide reference for the further analysis of localizer beacon.