Wavelet analysis approach to fault detection for GPS integrity monitoring

Reliability of a navigation system is one of greatimportance for navigation purposes. Therefore, anintegrity monitoring system is an inseparable part of aviation navigation system. Failures or faults due to malfunctions in the systems should be detected and repaired to keep the integrity of the system intact. In this paper, we present a method based on wavelet analysis for detecting failures. The raw pseudorange measurements are transformed by wavelet transform. Then the data jumping can be detected through the different wavelet scales. Therefore, the satellite fault could be detected. Two kinds of GPS satellite fault detection methods are given in detail, and the advantages and disadvantages of them are compared. Based on the wavelet analysis, the performance of fault detection is evaluated using the real measured data. The effectiveness of the proposed approach is illustrated in a problem of GPS (Global Positioning System) autonomous integrity monitoring system.