卫星导航地基增强系统(Ground Based Augmentation System,GBAS),可以提高卫星导航的精度、完好性、连续性和可用性,使飞机在复杂天气和恶劣环境下依然能够实现安全、高效的进近和着陆,满足民航精密进近和着陆引导等高精度导航需求.目前...卫星导航地基增强系统(Ground Based Augmentation System,GBAS),可以提高卫星导航的精度、完好性、连续性和可用性,使飞机在复杂天气和恶劣环境下依然能够实现安全、高效的进近和着陆,满足民航精密进近和着陆引导等高精度导航需求.目前GBAS一类精密进近(CATⅠ)服务水平已经完成验证和应用,但是其定位精度等服务水平仍不能完全满足民航需求.GBAS二类/三类精密进近(CATⅡ/Ⅲ)具有更好的服务水平,其技术和应用仍在开发验证中.为了提高民航运行效率和安全,急需开展基于CATⅡ/Ⅲ与CATⅢ的飞行校验活动.当前GBAS主要采用基于单频GPS的工作模式,在系统可用性、安全性和自主性方面非常受限,因此需要开发自主可控的兼容北斗的GBAS系统.本文设计了飞行校验方案,使用自主研制的国产GBAS设备,设计了飞行校验方案,在西安咸阳机场完成了CATⅡ/Ⅲ盲降精密进近着陆引导的GBAS飞行校验.试验结果表明:兼容北斗的国产GBAS具备支持CATⅡ/Ⅲ精密进近的能力,并且其性能远超传统仪表着陆系统(instrument landing system,ILS).这一成果的取得为我国航空运输的安全性提供了有力保障.展开更多
作为一种新型的、基于卫星导航系统的精密进近和着陆系统,地基增强系统(Ground Based Augmentation System,GBAS)与其他传统的地基无线电精密进近和着陆系统在系统构成和应用上有很大的不同,因此,GBAS系统飞行校验的方法和校验内容也和...作为一种新型的、基于卫星导航系统的精密进近和着陆系统,地基增强系统(Ground Based Augmentation System,GBAS)与其他传统的地基无线电精密进近和着陆系统在系统构成和应用上有很大的不同,因此,GBAS系统飞行校验的方法和校验内容也和这些传统的系统不一样。本文分析了在国内多个机场进行GBAS飞行试验的数据结果并据此对GBAS地面子系统的性能进行评估。结果显示GBAS系统可以满足CATI进近和着陆导航系统的精度要求,VDB信号覆盖和数据连续性也可以满足试验要求。展开更多
In this study,the gradients of Total Electron Content(TEC)for a midlatitude region are estimated and grouped with respect to the distance between neighboring stations,time periods within a day,and satellite directions...In this study,the gradients of Total Electron Content(TEC)for a midlatitude region are estimated and grouped with respect to the distance between neighboring stations,time periods within a day,and satellite directions.Annual medians of these gradients for quiet days are computed as templates.The metric distances(L2N)and Symmetric Kullback-Leibler Distances(SKLD)are obtained between the templates and the daily gradient series.The grouped histograms are fitted to the prospective Probability Density Functions(PDF).The method is applied to the Slant Total Electron Content(STEC)estimates from the Turkish National Permanent GPS Network(TNPGN-Active)for 2015.The highest gradients are observed in the east-west axis with a maximum of 25 mm/km during a geomagnetic storm.The maximum differences from the gradient templates occur for neighboring stations within100-130 km distance away from each other,during night hours,and for regions bordering the Black Sea and the Mediterranean in the northeast and southeast of Turkey.The empirical PDFs of the stationpair gradients are predominantly Weibull-distributed.The mean values of Weibull PDFs in all station groups are between 1.2 and 1.8 mm/km,with an increase during noon and afternoon hours.The standard deviations of the gradient PDFs generally increase during night hours.The algorithm will form a basis for quantifying the stochastic variations of the spatial rate of change of TEC trends in midlatitude regions,thus supplementing reliable and accurate regional monitoring of ionospheric variability.展开更多
文摘作为一种新型的、基于卫星导航系统的精密进近和着陆系统,地基增强系统(Ground Based Augmentation System,GBAS)与其他传统的地基无线电精密进近和着陆系统在系统构成和应用上有很大的不同,因此,GBAS系统飞行校验的方法和校验内容也和这些传统的系统不一样。本文分析了在国内多个机场进行GBAS飞行试验的数据结果并据此对GBAS地面子系统的性能进行评估。结果显示GBAS系统可以满足CATI进近和着陆导航系统的精度要求,VDB信号覆盖和数据连续性也可以满足试验要求。
基金supported by TUBITAK 112E568,114E092,and 115E915 projectsTNPGN-Active RINEX data set is available to the IONOLAB group for the TUBITAK 109E055 project。
文摘In this study,the gradients of Total Electron Content(TEC)for a midlatitude region are estimated and grouped with respect to the distance between neighboring stations,time periods within a day,and satellite directions.Annual medians of these gradients for quiet days are computed as templates.The metric distances(L2N)and Symmetric Kullback-Leibler Distances(SKLD)are obtained between the templates and the daily gradient series.The grouped histograms are fitted to the prospective Probability Density Functions(PDF).The method is applied to the Slant Total Electron Content(STEC)estimates from the Turkish National Permanent GPS Network(TNPGN-Active)for 2015.The highest gradients are observed in the east-west axis with a maximum of 25 mm/km during a geomagnetic storm.The maximum differences from the gradient templates occur for neighboring stations within100-130 km distance away from each other,during night hours,and for regions bordering the Black Sea and the Mediterranean in the northeast and southeast of Turkey.The empirical PDFs of the stationpair gradients are predominantly Weibull-distributed.The mean values of Weibull PDFs in all station groups are between 1.2 and 1.8 mm/km,with an increase during noon and afternoon hours.The standard deviations of the gradient PDFs generally increase during night hours.The algorithm will form a basis for quantifying the stochastic variations of the spatial rate of change of TEC trends in midlatitude regions,thus supplementing reliable and accurate regional monitoring of ionospheric variability.
