Research On GPS/BDS ARAIM Airworthiness Test Technology

As one of the four core indicators for evaluating navigation satellite systems,integrity is highly valued by the civil aviation field and is an important condition for ensuring the safe operation of civil aviation.Advanced Receiver Autonomous Integrity Monitoring(ARAIM)can perform horizontal and vertical integrity monitoring.Its performance is greatly improved compared to Receiver Autonomous Integrity Monitoring(RAIM).The airworthiness certification of ARAIM algorithm performance is an important part of ARAIM being put into civil aviation operations.At present,there is no internationally issued airworthiness standard about ARAIM.Therefore,this thesis mainly explores and researches the airworthiness test technology applicable to the combination of Global Positioning System(GPS)and BeiDou Navigation Satellite System(BDS).Contents are as follows.First,the definition of integrity,the integrity performance requirements for different approach phases specified by the International Civil Aviation Organization(ICAO),and the current three mainstream integrity monitoring methods are introduced in this thesis.Then the equivalence of the two RAIM algorithms is explained and the availability of RAIM is verified.Next,by studying the implementation process and principles of ARAIM,the architecture design of ARAIM and the ARAIM algorithm based on Multiple Hypothesis Solutions Separation(MHSS)are given.Then the method of failure mode determination in ARAIM algorithm is introduced in detail.Finally,using a suggested index as a reference,drawing on the airworthiness testing ideas of the GPS receiver RAIM algorithm performance in the technical standard document RTCA DO-208,the ARAIM fault detection and elimination performance testing process and ARAIM availability prediction performance testing process are designed.Based on the measured data,the fault detection and elimination performance of ARAIM,the impact of Integrity Support Message(ISM)on the vertical protection level,the availability prediction performance of ARAIM are tested and analysed under the GPS/BDS combined system.The test results are as follows.The ARAIM algorithm has a high efficiency for fault detection and elimination,and the probability of correct detection and elimination reaches 99.9%.Although the user range accuracy and satellite failure probability in ISM will affect the size of the vertical protection level,but the user range accuracy has a greater impact on the vertical protection level.The user range accuracy largely determines the availability of the system.In single points and routes,the availability prediction results of ARAIM always meet the integrity performance requirements of LPV-200.In China,the availability coverage rate of ARAIM reaches 99%.In Asia-Pacific region and worldwide,the availability prediction results of ARAIM in some regions cannot meet the integrity performance requirements of LPV-200,but the availability coverage rate also reaches more than 90%.