大规模低轨星座多普勒定位算法

Doppler Positioning Performance of LEO Mega Constellation

基于典型的Starlink星座构型,对大规模低轨星座多普勒定位算法展开研究。实验结果表明,理想条件下低轨星座多普勒单点定位精度可以在3~6 m。为保证米级的定位精度,低轨卫星的位置精度和速度精度应为米级每秒或厘米级每秒。C频段信号受到的电离层误差若不做改正,将导致定位精度变差2 m左右。对流层误差将使得定位结果变差几十米。此外,使用轨道高度为550 km的低轨卫星的多普勒频移定位时,接收机的初值误差应小于300 km,否则部分历元将不能收敛到正确的接收机位置。

This paper proposed a Doppler-only point-solution algorithm and analyzed the Doppler positioning performance based on the Starlink constellation.The Doppler positioning accuracy was about 3~6 m.To achieve the meter-level positioning accuracy,the satel-lite position and velocity errors should be within several meters and several centimeters per second,respectively.The ionospheric delay rates of C-band signal would cause about 2 m error in Doppler positioning.The positioning error would increase by dozens of meters if there were no corrections for the tropospheric errors.To ensure convergence in the LEO-based Doppler positioning,the initial receiver position error should be less than 300 km when the satellites orbit at an altitude of 550 km.