Integrity Technique Based On GPS Attitude Determination

Along with the improvement of positioning precision basing on GPS, the attitudedetermination technique with GPS has come into being. Meanwhile, integrityperformance is the key to assure the stringent safety requirements of navigationsystem, and to take GPS as the sole-means navigation．This paper focuses on the GPSReceiver Autonomous Integrity Monitoring (RAIM). The problem relating to thistechniques, such as theory, system designation， algorithms and so on，are studiedsystematically．Firstly, this paper introduces the system composing of GPS, positioning theory,carrier phase measurement theory, error sources of GPS measurement and thecorresponding resolving means. Then discusses the attitude determination theory indetail, and introduces the related coordinate systems, the conversion relationship ofthe coordinate systems, observation equations of carrier phase and so on. Ambiguitysolution which is the key technique of carrier phase measurement is also discussed inthis paper.RAIM algorithm is analyzed as well. There are two main methods based onleast-square residual method and parity vector method respectively. Thecorresponding fault-detecting and fault-excluding models are deducted. These twomethods are proved to be equivalent in theory. Also, least-square residual RAIM isexperienced using real data.RAIM algorithm is programmed in simulation environment which demonstratesits contribution to the stability and reliability of the system. In the last, the paperintroduces the experiments in attitude determination. Results of this system isanalyzed, the precision of the system can be up to0.1°to0.2°rms.