IMPROVED FILTER TYPE INTEGRITY MONITORING IN SATELLITE NAVIGATION

摘要

Compared with the conventional least-squares-residuals method, the proposed filter type method, namely the exponentially weighted moving average (EWMA) filter, can achieve the goal of fast satellite failure detection in receiver autonomous integrity monitoring (RAIM). The corresponding threshold of the EWMA filter can be computed offline via the Markov chain approximation. Some modifications made in the EWMA filter are also introduced in this paper. Simulation results show that by choosing the weighting factor properly the detection time can be considerably reduced.