Robustness Enhancement of GPS Vector Tracking Loop Using the Fault Detection and Exclusion Algorithm

Abstract

Although the vector tracking loop architectures provide several important advantages, they suffer some fundamental drawbacks. The most significant drawback is that failure of tracking in one channel may affect the entire system and lead to loss of lock on all satellites. The other drawback is that errors in the navigation solutions may degrade the accuracy of the tracking results. For robustness improvement of the vector tracking loop, the EKF based receiver autonomous integrity monitoring (RAIM) and fault detection and exclusion (FDE) algorithms are developed to prevent the error of one channel from spreading into the vector tracking loop. The RAIM is used to check the possible fault in the pseudorange and the pseudorange rate; the fault detection and exclusion mechanism is employed for excluding the abnormal satellite signal to prevent the failure of one channel from spreading into the entire tracking loop. The feasibility of the proposed method will be demonstrated. Performance assessment and evaluation for the proposed approach will be carried out.