北斗卫星钟差数据质量评估与特性分析OA

The satellite clock offset are an important data source for the study of GNSS and satellite clock-related technolo-gies.In order to comprehensively analyze the quality and characteristics of BeiDou satellite clock offset,a data quality assessment scheme to eliminate systematic bias and additional orbit error correction is proposed,the data quality of various clock products based on orbit determination and time synchronization(ODTS)solving is evaluated,and the commonalities and differences between clock offset based on the star-ground bidirectional time-transfer(TWTT)and the ODTS system are analyzed.The results of case analysis show that the GBM product provides comprehensive sub-nanosecond BeiDou clock offset with the best integrated quality,which is suitable for the long-term characterization of satellite clocks.The accuracy of the iGMAS ultra-fast clock offset is nanosec-ond and the efficiency is low,so there is an urgent need to study the corresponding high-precision clock offset prediction method.The noise levels of the TWTT and ODTS based clock difference data are affected by the orbit and have different periodicity character-istics,and the stability curves of the two systems have similar time-dependent trends,and both of them have anomalous bulges.