ARAIM Algorithm Of Airborne Receiver Based On BDS/GPS

With the rapid development of the Global Navigation Satellite System(GNSS),in the civil aviation field where life and safety services are highly demanded,integrity has become a key indicator of civil aviation navigation systems.From the takeoff,route,terminal area to the approach phase,the aircraft needs to meet the required navigation performance(RNP)integrity requirements.The precision approach phase is to satisfy the performance-based navigation(PBN),and the accuracy in the vertical direction needs to meet the integrity requirements of this phase.Non-precision approaches do not have this feature.The Advanced Receiver Autonomous Integrity Monitoring Technology(ARAIM)supports the aircraft's decision-making height of 200 ft vertical guidance,the LPV-200,through an integrity algorithm.The thesis firstly introduces the ARAIM operating level LPV-200,the concept of ARAIM,the source of positioning error and the type of satellite fault caused by error.Then,the parity vector method in the typical RAIM integrity algorithm is introduced.This method has better detection for the case where there is only single satellite fault,but in the multi-navigation system,multiple satellites simultaneously with multiple satellite faults can't be ignored.lastly,the multiple hypothesis solution separation(MHSS)algorithm and fault detection principle are described.The advantages and disadvantages of the algorithm are described and summarized,and the ARAIM algorithm is optimized.According to the similar physical properties of different satellites in the same orbit,a fault detection algorithm based on satellite orbit packet is proposed.The algorithm can reduce the direction cosine matrix and reduce the computational complexity of the MHSS algorithm.Compared with the traditional RAIM integrity algorithm,it has higher fault detection efficiency.