顾及不同天线相位中心改正模型的北斗空间信号精度评估方法

BDS Signal-in-Space User Range Error Evaluation Considering Different Antenna Phase Center Offset Models

IGS各分析中心提供的北斗精密轨道和精密钟差产品可能因采用不同的天线相位中心模型而存在一定差异,其对精密产品之间的比较以及利用精密产品评估北斗空间信号精度会产生一定影响。首先利用实测观测数据深入分析了采用不同天线相位中心改正模型对精密轨道和钟差的影响规律,在此基础上提出了顾及不同天线相位中心改正模型的北斗空间信号精度评估方法,以欧洲定轨中心、德国地学中心、武汉大学提供的精密轨道和钟差作为参考,对北斗广播轨道、广播钟差以及空间信号精度进行了分析和比较。结果表明,在考虑了卫星天线相位中心改正模型的差异之后,采用不同分析中心提供的北斗精密轨道和精密钟差作为基准评估出的空间信号精度基本一致,地球同步轨道卫星优于1.68 m,倾斜地球同步轨道卫星优于0.78 m,中地球轨道卫星优于0.66 m,验证了所提出的评估方法的正确性。

BDS precise orbit and precise clock products provided by IGS analysis centers may differ due to the use of different antenna phase center models, which has a great impact on the comparison between precise products and the use of precise products to evaluate the accuracy of the BDS signal-in-space user range error. In this paper, the influence of different antenna phase center correction models on the precise orbit and clock products is analyzed in depth by using the measured observation data. Based on this, the BDS signal-in-space user range error evaluation method is proposed considering different antenna phase center correction models. With the precise orbit and clock products provided by the Center for Orbit Determination in Europe(CODE), Deutsches GeoForschungs Zentrum(GFZ) and Wuhan University(WHU),we evaluate the broadcast orbit,broadcast clock and signal-in-space user range error. The results show that after considering the difference of the satellite antenna phase center correction model, the accuracy of the signal-in-space user range error evaluated by the BDS precise orbit and precise clock products provided by different analysis centers is basically the same. Geostationary orbit is better than 1.68 m, inclined geosynchronous orbit is better than 0.78 m, medium earth orbit is better than 0.66 m, which verifies the correctness of the evaluation method proposed in this paper.