导航卫星星地/星间链路联合精密定轨及钟差解算时,若星间测距信号和下行导航信号设备时延不一致,将会以系统误差的形式影响解算结果.为保持与用户算法一致性,提出利用星间测距数据求解的卫星钟差也应该包含导航信号设备群时延.基于此,建立了联合定轨中估计星间链路设备时延改正数的星间测距观测方程,设计出在定轨和钟差解算的同时估计设备时延改正数的两种数据处理方案:一是估计每颗卫星的接收和发射时延改正数;二是估计每条(有向)链路的时延改正数.通过仿真试验证明上述两种方案的正确性和可行性,试验结果表明上述方案可显著降低设备时延对轨道和钟差解算精度的影响.%The difference between equipment delays of inter-satellite ranging signal and naviga-tion signal would consequentially impact on the result of orbit determination and clock solution solved with inter-satellite ranging data and observations from ground-based monitoring stations. In order to keep consistent with GNSS user algorithms for positioning and timing,it’s pointed out that the satellite clock bias solved with inter-satellite ranging observations should also include the group delay (GD)of navigation payload onboard GNSS satellites,and the observation equa-tions are derived for combined orbit determination.The method for dealing with the problem of e-quipment delay is discussed.It is pointed that equipment delays should be estimated via data processing.Two approaches for data processing are proposed:one is to estimate the delay cor-rection parameters for each satellite;another is to estimate the delay correction parameters for each (directional-)link.Software for simulation and data processing has been developed and the feasibility of the proposed method and data processing strategy are validated by simulation analysis.The results indicate that,by applying anyone of the two proposed approaches,the accuracy of orbit and clock result could be significantly improved and the effect is nearly the same as if the equipment delays have been exactly corrected.
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