Research And Implementation Of Key Technologies For Satellite Navigation Monitoring

GNSS is widely used in military security,national economy and daily life because GNSS can provide users with all-weather,continuous navigation,positioning and timing services.In order to improve the user experience,the major satellite navigation systems are constantly improving the system's performance and service capabilities.However,due to various interference factors,sudden state,design defects and system failure,these conditions have a great impact on the service capability of satellite navigation system.In this context,in order to ensure the reliability and security of future satellite navigation applications.It is necessary to establish a set of well-functioned monitoring methods,which can provide timely and reliable early warning in case of system problems and ensure the service capability of satellite navigation system.Navigation monitoring technology mainly includes constellation performance monitoring,space signal quality monitoring,navigation information monitoring and navigation service performance monitoring.According to the monitoring object,it mainly includes receiver level monitoring,station level monitoring and system level monitoring.This paper analyses the emergence and development status of navigation monitoring technology,expounds the basic concept,monitoring purpose,monitoring content and monitoring methods of navigation monitoring technology,and introduces such monitoring technologies as constellation performance monitoring,space signal quality monitoring,navigation information monitoring and navigation service performance monitoring.This paper studies the constellation usability of four navigation systems separately,and makes a thorough study on different systems and different constellation deployment schemes and draws relevant conclusions.Through gross error elimination and quality control,the navigation observation is monitored and processed,and gross error elimination prevents the problem data from entering the system and affects the normal judgment of the system.Quality control guarantees data quality and prevents abnormal data from causing system failure detection.Two methods are used to monitor the correctness of navigation message.One is threshold monitoring method.Through long-time actual observation,the variation law of ephemeris orbit parameters is counted,and the corresponding threshold range table of parameters is drawn up.The other is the method of satellite coordinate comparison,which calculates the position of satellite at the same time by using the ephemeris of two adjacent groups of satellites,and determines the correctness of navigation messages by comparing the coordinates of two groups of satellites.At the same time,the system-level monitoring is deeply studied,and the principle of minority obeying majority is put forward to distinguish,which eliminates the monitoring anomalies caused by intentional interference of single receiver or single monitoring station This paper makes a useful exploration on system-level monitoring,establishes a navigation monitoring platform based on the research results of domestic navigation monitoring technology,and summarizes its application.Research work of this paper is the follow-up navigation monitoring techniques deeper foundation.