An Improved RAIM Algorithm on Simultaneous Two-Faulty Satellites

Due to the presence of missing detection and false alarm resulting in a lower recognition rate in the traditional fault recognition algorithm which is based on thresholds recognition, this paper proposes an improved RAIM algorithm on simultaneous two-faulty satellites which is on the basis of QR decomposition fault features plane. The algorithm identifies the characteristics of satellite failures by using the geometric relationship between the parity vector and the fault plane, which makes it beyond the limit of the impact of recognition thresholds and thereby effectively avoid lw identification efficiency because of the recognition thresholds. This paper conducts detailed analysis on the specific processes and characteristics of fault identification by the algorithm and simulation analysis on its performance. Compared with the optimal parity vector method and remodeling optimal parity vector method, the fault identification rate by this method increases significantly, compared with simultaneous two-faulty satellites method before the improvement, this method shows a similar fault identification rate, but a decrease of the calculation time by 17.34%, and therefore it improves the overall performance.