摘要
目前,在轨的5颗新一代北斗卫星(北斗三号)可同时向用户播发北斗二号信号与新的卫星信号,而且北斗三号搭载了高精度的铷钟或被动氢钟.因北斗三号的星钟作为卫星导航、定位和授时服务的主要载荷组成部分,为分析北斗三号卫星钟的时频性能,采用北斗数据处理与分析中心估计的卫星钟差产品评估北斗三号卫星钟的频率稳定度、漂移率和准确度.同时,考虑到北斗三号卫星钟精度较差且存在频繁的相位跳变以及数据中断等问题,筛选出了一种最优的钟差预报模型,即对频率数据进行建模并采用抗差估计的方法进行参数估计.实验结果显示北斗三号钟差预报精度相对传统预报模型提升1.6%–61.9%.
Currently, five BDS-3 satellites are transmitting both the BDS-2 signals and new signals for BDS-3. They are equipped with high-precision rubidium or/and passive hydrogen maser clocks. These clocks constitute the major payloads that are responsible for the BDS-3＇ positioning, navigation, and timing services. To analyze the performance of time-frequency, the clock offset products, which are estimated by the BeiDou Data Processing and Analysis Centers, are used to evaluate the frequency stability, drift rate, and accuracy. Given the low precision of these clock products, as well as frequent phase transition and data missing, this study develops an optimal prediction model to predict the BDS-3 clocks which is based on the modelling of the frequency data, and adopts a robust algorithm in parameters estimation. The results show that the improvements of the prediction accuracies of BDS-3 clock offsets are from 1.6% to 61.9%.
出处
《天文学报》
CSCD
北大核心
2018年第1期56-69,共14页
Acta Astronomica Sinica
基金
国家自然科学基金项目(41404033)
国家重点实验室开放基金项目(SKLGIE2014-Z-1-1)资助
