A Detection Method of the Ionosphere Anomaly in SBAS
【摘要】：In order to detect the slow varying ionosphere anomaly existing in the GNSS measurements in SBAS, an algorithm based on the carrier phase is proposed. On the basis of the analysis of the feature of ionosphere delay, the carrier-phase measurements with high accuracy is applied to reconstruct a temporal rate of ionosphere delay. Then, the temporal rate is processed by an adaptive filter to prevent it from the influence from the ionosphere anomaly. Finally, a virtual ionosphere delay vulnerable to the anomaly is established. A test variable for detecting the anomaly is set up by combining the real delay with the virtual delay and the hypothesis test method is utilized to check if there is an ionosphere anomaly. Based on the real measurements, the corresponding simulation is implemented and the results demonstrate that the algorithm proposed in the paper has a significant improvement on the detection speed. Furthermore, the effect on the estimates of the ionosphere corrections from the anomaly is greatly eliminated.