Impact Analysis of BeiDou Satellite Integrity Events in 2022

With the completion of the technical revision of BeiDou System in international civil aviation standards, the accuracy, continuity, integrity of BeiDou System will become the focus of global civil aviation users. During the assessment of the BeiDou open service performance, it was found that in March 2022, the BDS- 3 MEO-3 (PRN21) satellite had a serious abnormal event. The event occurred in which PRN21 satellite had a frequency offset fault of the satellite clock and last-ed 20 h. The satellite clock error in the event produced a slope fault of 0.76 m/s, and the maximum satellite clock error reached 36616 m. According to the B1I signal message health identifier, the events are divided into 13 h of integrity events and 7 h of continuity events. In accordance with the performance evaluation methods stipulated in the international civil aviation standards, the accuracy, continuity and integrity of the BeiDou satellite space signal performance were evaluated in this quarter. The results show that the single satellite integrity risk of the system in the quarter caused by the event is 2.23 × (10(−4)), and the continuity risk of PRN21 satellite is 0.398%, both of which are far higher than the ones in the same quarter in 2021. Receiver Autonomous Integrity Monitoring (RAIM) was performed to monitor the faults, and the algorithm achieved fault detection and recognition when the satellite clock error reached 16m which meet the integrity requirements of enroute, terminal, NPA. Based on the analysis of this incident, reasonable suggestions are put forward for the aviation application of the BeiDou System.