The Research Of Optimization RAIM Algorithm Based On The Risk Of Integrity

Receiver autonomous integrity monitoring(RAIM)is the algorithm designed for the dynamic navigation receiver,which could detect and insulate the satellite fault by using redundant observation.RAIM has the advantage of response to abnormal observation rapidly and independently without external monitoring station network.So that it is necessary for processing steps in the process of dynamic navigation.This paper researches the processing methods for the gross error observation on account of the integrity risk of RAIM,the main study of the following:(1)the optimal robust least squares estimation;(2)the optimization of detection algorithm for single fault based on the least squares RAIM;(3)the optimization of detection algorithm for double fault based on the parity vector algorithm.First of all,this paper summarizes the research status at home and abroad of receiver autonomous integrity monitoring and robust estimation.Then,introduces the theoretical basis of RAIM respectively,including the GNSS navigation and positioning error,the parameter estimation method and the hypothesis testing method.Secondly,introduces the robust estimation method and analyze and contrast the design methods of the equivalent weight function,and put forward the equivalent weight function optimization design method of modulation coefficient,the effectiveness of the optimization method is verified by simulation experiment.Thirdly,introduces the RAIM algorithm based on the least squares estimate and the potential integrity risk.This paper proposes an optimal non-equal sliding window accumulation algorithm for the integrity risk based on the error-test slope of satellite combined with the advantage of the accumulation algorithm and the performance of the optimal method is test and verified by simulation.Finally,introduces the principle of the advanced receiver autonomous integrity monitoring(ARAIM),in view of the insufficient of the performance of the traditional parity vector algorithm and the disadvantage of the large amount of calculation of the parity vector geometry algorithm,this paper proposes a parity vector solution separation algorithm for the recognition of binary fault combining the ARAIM and the simulation analysis verity the feasibility of the algorithm.