Theory And Technique Research On GNSS Intergrity

With GNSS technology in the world of rapid development, GNSS technology in thepublic transport industry, particularly in the life safety has been widely used.Andpeople in theintegrity of GNSS navigation performance requirements become more stringent, in order toprotect the safety of navigation and positioning. Therefore, this paper carried out a series ofstudies in this regard, the main research work and achievements are as follows：（1）The current GNSS integrity monitoring technology theory and methods is studied.And it will be divided into satellite segment integrity monitoring, ground segment integritymonitoring, and receiver integrity monitoring. This paper focuses on the ground and clientintegrity monitoring techniques: the receiver autonomous integrity monitoring, wide areaaugmentation system integrity monitoring and Galileo system integrity monitoring technology,and we studied their algorithms and related issues.（2）This paper discusses the receiver autonomous integrity monitoringmodel andalgorithm, and pointed out that GPS/GLONASS combinations is better than GPSinavailability and GPS RAIM hole forecasts. Based on RAIM algorithm, we introduce a RAIMalgorithm based on sliding window. And simulation results show that the algorithm is betterthan the ordinary RAIM algorithm in availability, or fault detection andfault identification.Finally, we introduce the time measurement integrity monitoring theory and methods. Bycomparing the RAIM algorithm based on sliding window of the new algorithm with theordinary time measurement integrity algorithm, we find that the sliding window RAIMalgorithm still has the great advantage of the indicators.（3）We introduc the wide area augmentation system integrity monitoring theory and themain parametersUDRE、GIVE. And we analyze the model and algorithm of the associatedparametersRURA、UIVE.Thesimulation analysis of aboveintegrity parameters shows thatbecause of the number of reference stations in the case of fewer, UDRE and GIVE appearunavailable in some areas. So it can not meet the requirements of WAAS.（4）In this paper, Galileo system integrity monitoring system is described in detail, andwe givethe key indicators parameters of Galileo system integrity monitoring:Signal-In-Space Error(SISE),Signal-In-SpaceAccuracy(SISA), Signal-In-Space Monitoring Accuracy(SISMA).The simulation analysis of these three parameters shows that, using only a small number ofmonitoring stations, can not meet the Galileo system integrity monitoring requirements.Butwe can increase the number of monitoring stations to improve the integrity monitoringindicators.