Detection of multiple faults in single-frequency differential GPS measurements

For reliable application of GPS, multiple fault detection is one of the most serious concerns demanding a practical solution. Multiple faults occurring at the same time cannot be detected by simple position domain residual detectors or parity vectors since they bear the possibility of cancelling each other. For differential positioning based on single-frequency receivers, this study proposes an efficient fault detection method. The proposed method consists of three different detectors: the range domain signal fault detector, the abnormal ephemeris detector and the double differenced position domain residual detector. Owing to diverse viewpoints provided by the three different detectors, detection and identification of multiple faults is facilitated. To evaluate the performance of the proposed method, simulation and experiment results are demonstrated.