Satellite integrity monitoring is vital to satellite-based augmentation systems,and can provide the confdence of the diferential corrections for each monitored satellite satisfying the stringent safety-of-life require...Satellite integrity monitoring is vital to satellite-based augmentation systems,and can provide the confdence of the diferential corrections for each monitored satellite satisfying the stringent safety-of-life requirements.Satellite integrity information includes the user diferential range error and the clock-ephemeris covariance which are used to deduce integrity probability.However,the existing direct statistic methods sufer from a low integrity bounding percentage.To address this problem,we develop an improved covariance-based method to determine satellite integrity information and evaluate its performance in the range domain and position domain.Compared with the direct statistic method,the integrity bounding percentage is improved by 24.91%and the availability by 5.63%.Compared with the covariance-based method,the convergence rate for the user diferential range error is improved by 8.04%.The proposed method is useful for the satellite integrity monitoring of a satellite-based augmentation system.展开更多
The ionosphere is the ionized part of the upper atmosphere of the Earth,which plays an important role in atmospheric electricity and forms the inner edge of the magnetosphere.It influences radio propagation significan...The ionosphere is the ionized part of the upper atmosphere of the Earth,which plays an important role in atmospheric electricity and forms the inner edge of the magnetosphere.It influences radio propagation significantly,such as the Global Navigation Satellite System(GNSS).Meanwhile,the GNSS is also an essential technique for sensing the variation of ionosphere.During the years of 2019—2023,a large number of Chinese geodesy scientists devoted much efforts to the geodesy related ionosphere.Due to the very limited length,the achievements are carried out from the following six aspects,including:①The ionospheric correction models for BDS and BDSBAS;②Real-time global ionospheric monitoring and modeling;③The ionospheric 2D and 3D modeling based on GNSS and LEO satellites;④The ionospheric prediction based on artificial intelligence;⑤The monitoring and mitigation of ionospheric disturbances for GNSS users;⑥The ionospheric related data products and classical applications.展开更多
Several noteworthy breakthroughs have been made with the BeiDou Navigation Satellite System(BDS)and other global navigation satellite systems as well as the associated augmentation systems,such as the commissioning of...Several noteworthy breakthroughs have been made with the BeiDou Navigation Satellite System(BDS)and other global navigation satellite systems as well as the associated augmentation systems,such as the commissioning of the BDS-3 preliminary system and the successful launch of the first BDS-3 GEO satellite which carries the satellite-based augmentation payload.Presently,BDS can provide basic services globally,and its augmentation system is also being tested.This paper gives an overview of BDS and satellite navigation augmentation technologies.This overview is divided into four parts,which include the system segment technologies,satellite segment technologies,propagation segment technologies,and user segment technologies.In each part,these technologies are described from the perspectives of preliminary information,research progress,and summary.Moreover,the significance and progress of the BeiDou Satellite-based Augmentation System(BDSBAS),low earth orbit augmentation,and the national BeiDou ground-based augmentation system are presented,along with the airborne-based augmentation system.Furthermore,the conclusions and discussions covering popular topics for research,frontiers in research and development,achievements,and suggestions are listed for future research.展开更多
基金supported by the Research Startup Funds from Tianjin University of Technology under Grant 01002101.
文摘Satellite integrity monitoring is vital to satellite-based augmentation systems,and can provide the confdence of the diferential corrections for each monitored satellite satisfying the stringent safety-of-life requirements.Satellite integrity information includes the user diferential range error and the clock-ephemeris covariance which are used to deduce integrity probability.However,the existing direct statistic methods sufer from a low integrity bounding percentage.To address this problem,we develop an improved covariance-based method to determine satellite integrity information and evaluate its performance in the range domain and position domain.Compared with the direct statistic method,the integrity bounding percentage is improved by 24.91%and the availability by 5.63%.Compared with the covariance-based method,the convergence rate for the user diferential range error is improved by 8.04%.The proposed method is useful for the satellite integrity monitoring of a satellite-based augmentation system.
基金National Key R&D Program of China(No.2021YFB3901301)National Natural Science Foundation of China(Nos.42074043,42122026,42174038)Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.Y9E006033D)。
文摘The ionosphere is the ionized part of the upper atmosphere of the Earth,which plays an important role in atmospheric electricity and forms the inner edge of the magnetosphere.It influences radio propagation significantly,such as the Global Navigation Satellite System(GNSS).Meanwhile,the GNSS is also an essential technique for sensing the variation of ionosphere.During the years of 2019—2023,a large number of Chinese geodesy scientists devoted much efforts to the geodesy related ionosphere.Due to the very limited length,the achievements are carried out from the following six aspects,including:①The ionospheric correction models for BDS and BDSBAS;②Real-time global ionospheric monitoring and modeling;③The ionospheric 2D and 3D modeling based on GNSS and LEO satellites;④The ionospheric prediction based on artificial intelligence;⑤The monitoring and mitigation of ionospheric disturbances for GNSS users;⑥The ionospheric related data products and classical applications.
基金the National Natural Science Foundation of China(No.61571309)Talent Project of Revitalization Liaoning(No.XLYC1907022)+1 种基金Natural Science Foundation of Liaoning Province(No.2019-MS-251)High-Level Innovation Talent Project of Shenyang(No.RC190030).
文摘Several noteworthy breakthroughs have been made with the BeiDou Navigation Satellite System(BDS)and other global navigation satellite systems as well as the associated augmentation systems,such as the commissioning of the BDS-3 preliminary system and the successful launch of the first BDS-3 GEO satellite which carries the satellite-based augmentation payload.Presently,BDS can provide basic services globally,and its augmentation system is also being tested.This paper gives an overview of BDS and satellite navigation augmentation technologies.This overview is divided into four parts,which include the system segment technologies,satellite segment technologies,propagation segment technologies,and user segment technologies.In each part,these technologies are described from the perspectives of preliminary information,research progress,and summary.Moreover,the significance and progress of the BeiDou Satellite-based Augmentation System(BDSBAS),low earth orbit augmentation,and the national BeiDou ground-based augmentation system are presented,along with the airborne-based augmentation system.Furthermore,the conclusions and discussions covering popular topics for research,frontiers in research and development,achievements,and suggestions are listed for future research.
