仪表着陆系统信号质量分析

AbstractInstrument Landing System (ILS),as an advanced navigation system,is used toguide aircraft approach and landing,and has been widely used in airports around theworld.The change of the critical and sensitive area will interfere with the space signaland affect flight safety.Therefore,the definition and protection of key and sensitive areasplay an important role in ensuring the safety of aircraft landing,optimizing airportairspace and capacity limitation.With the deterioration of the electromagneticenvironment around the airport and the improvement of operational performancecategory,higher requirements are put forward for setting the key sensitive areas ofinstrument landing system..Firstly,starting from the composition and influencing factors of the critical and sensitivearea,the setting of ILS critical and sensitive area in different countries are introduced,and the differences are analyzed by comparison.Secondly,based on the modeling of keysensitive area,the influence of various obstacles and terrain on the spatial signal isanalyzed.The influences of the static obstacles and dynamic obstacles on the routestructure and signal coverage at different operational performance categories areanalyzed in detail,and the spatial signal are optimized through system selection.Inaddition,the influence of the critical and sensitive area on the glide slope position and theinfluence of airport enclosure on the glide slope structure were analyzed.Three types ofantennas have the same adaptability to the field environment.On the basis of the abovetheoretical analysis,combined with the actual airport environment and the flightverification conclusions,the spatial signal of various obstacles affecting ILS aresimulated.By system selection or internal adjustment to avoid obstacles,the method ofimproving signal quality is put forward,and feasible suggestions for setting key sensitiveareas of blind drop are put forward.Keywords:Instrument landing system,Signal strength,Critical area,Sensitive area,Spatial signal,Influence factor analysis,Simulation application-i-