Clock-based RAIM method and its application in GPS receiver positioning

Because the signals of global positioning system （GPS） satellites are susceptible to obstructions in urban environment with many high buildings around, the number of GPS useful satellites is usually less than six. In this case, the receiver autonomous integrity monitoring （RAIM） method earmot exclude faulty satellite. In order to improve the performance of RAIM method and obtain the reliable positioning results with five satellites, the series of receiver clock bias （RCB） is regarded as one useful satellite and used to aid RAIM method. From the point of nonlinear series, a grey-Markov model for predicting the RCB series based on grey theory and Markov chain is presented. And then the model is used for aiding RAIM method in order to exclude faulty satellite. Experimental results demonstrate that the prediction model is fit for predicting the RCB series, and with the clock-based RAIM method the faulty satellite can be correctly excluded and the positioning precision of GPS receiver can be improved for the case where there are only five useful satellites.

Because the signals of global positioning system(GPS) satellites are susceptible to obstructions in urban environment with many high buildings around,the number of GPS useful satellites is usually less than six.In this case,the receiver autonomous integrity monitoring(RAIM) method cannot exclude faulty satellite.In order to improve the performance of RAIM method and obtain the reliable positioning results with five satellites,the series of receiver clock bias(RCB) is regarded as one useful satellite and used to aid RAIM method.From the point of nonlinear series,a grey-Markov model for predicting the RCB series based on grey theory and Markov chain is presented.And then the model is used for aiding RAIM method in order to exclude faulty satellite.Experimental results demonstrate that the prediction model is fit for predicting the RCB series,and with the clock-based RAIM method the faulty satellite can be correctly excluded and the positioning precision of GPS receiver can be improved for the case where there are only five useful satellites.