相位单差残差评估北斗区域导航系统载波相位观测量质量

Quality Assessment of Carrier Phase Observable for BeiDou Regional Satellite Navigation System Based on the Single-Difference Phase Residuals

由于北斗区域导航系统采用混合星座设计,其不同类型卫星载波相位观测量的质量得到广泛关注。当基线较短且模糊度正确固定后,卫星残差信息可有效反映观测数据质量。本文采用优化的站际单差算法获取不同卫星单差残差序列,并对其进行统计分析与假设检验。结果表明,北斗GEO与IGSO卫星数据质量无系统性差异,其质量随卫星高度角的降低而明显变差。良好环境下,GEO与IGSO卫星相位单差残差基本服从正态分布,可依据卫星高度角等信号质量指标建立合适的随机模型。

The quality of carrier phase observable of BeiDou satellites has attracted widespread attention because of the hybrid constellation design which is composed of the GEO,IGSO and MEO satellites.Considering that the residual is effective to reflect the signal quality when the ambiguities have been fixed correctly in short baseline positioning,the optimized algorithm of single-difference （SD） is adopted to achieve the residuals in this paper.After taking the data analysis,and statistics and hypothesis testing,the result shows that there is no systemic difference between GEO and IGSO satellite signal and the data quality decreases with decreasing satellite elevation.Furthermore,the residuals of the GEO and IGSO satellites obey the normal distribution in the open-sky environment.Therefore,a suitable stochastic model can be established based on the quality indexes such as elevation angles.