GNSS观测噪声对低轨卫星轨道确定的影响分析

Analysis of the influence of GNSS observation noise on the orbit determination of LEO satellites

低轨卫星不仅是实现全球通信的重要手段,也是对地观测研究的重要平台。利用全球卫星导航系统(GNSS)确定高精度的轨道是实现低轨卫星各项功能的重要基础。为了研究GNSS观测噪声对低轨卫星定轨精度的影响,该文通过模拟包含不同量级观测噪声的GNSS观测值,分析了GNSS观测噪声对运动学定轨和动力学定轨结果的影响。实验结果表明,在伪距噪声量级优于0.6 m、载波相位噪声量级优于2 mm时,运动学定轨与动力学定轨结果相当,且都在毫米级;在伪距噪声量级为6 m、载波相位噪声量级为厘米级时,运动学定轨结果达到厘米级,而动力学定轨结果仍然为毫米级,体现出了相对于运动学定轨的优越性;载波噪声相对伪距噪声对定轨结果的影响更大。

Low Earth orbit(LEO)satellites are not only an important means to achieve global communication,but also an important platform for earth observation research.Using the global navigation satellite system(GNSS)to determine high-precision orbits is an important basis for realizing various functions of LEO satellites.In order to study the influence of GNSS observation noise on the orbit determination accuracy of LEO satellites,in this paper,by simulating GNSS observations containing different levels of observation noise,the influence of GNSS observation noise on the results of kinematic and dynamic orbit determination was studied and analyzed.The experimental results showed that when the magnitude of pseudorange noise was better than 0.6 m,and the magnitude of carrier phase noise was better than 2 mm,the results of kinematic orbit determination were equivalent to that of dynamic orbit determination,and both were at the millimeter level.When the magnitude of pseudorange noise was 6 m,and the carrier phase noise level was centimeter level,the kinematic orbit determination result could reach centimeter level,while the dynamic orbit determination result was still millimeter level,which showed the superiority over kinematic orbit determination.Carrier phase noise had a greater impact on orbit determination results than pseudorange noise.