北斗卫星导航系统实时定轨与钟差处理策略

BDS Satellite Real Time Orbit and Clock Determination and Initial Results Analysis

目前鲜有对北斗卫星导航系统（BeiDou Navigation Satellite System,BDS）实时精密定轨与钟差确定的研究,文章提出了BDS实时轨道与实时钟差处理策略,包括了观测与动力学模型、实时轨道与实时钟差处理流程与评估方法。尤其对于实时钟差,为了提高计算效率,联合使用两个独立并行的线程估计非差绝对钟差和历元间相对钟差。利用多模全球卫星导航系统试验（MGEX）与全球连续检测评估系统（iGMAS）实测数据进行了北斗实时轨道与钟差解算,BDS实时轨道径向平均精度对于GEO卫星优于20 cm,对于IGSO与MEO一般优于10cm;钟差精度对于GEO卫星为0.5~4.5ns,对于IGSO/MEO为0.2~2.0ns。基于目前的轨道与钟差结果,实时精密单点定位（Precise Point Positioning,PPP）结果可以达到分米量级。

Navigation satellite real time orbit determination and clock determination are research highlights in navigation areas.The processing strategies and processes for Beidou Navigation Satellite System（BDS） real time orbit determination and clock determination were provided,especially for the clock processing with zero-differenced absolute clock and epoch-differenced relative clock.Using the data from the Multi-GNSS Experiment（MGEX） and international GNSS monitoring Assessment Service（iGMAS） tracking networks,the average orbit accuracy for real time BDS in radial direction is better than 20 cm,and 10 cm for GEO,IGSO and MEO,respectively.And the clock accuracy for real time BDS can reach 0.5~4.5 ns,and 0.2~2.0 ns for GEO,IGSO and MEO,respectively.Based on the this result,the real time precise pointing position（PPP）performance following BDS can achieve decimeter level.