Single Satellite Positioning Error Analysis and Performance Simulation Based on LEO Constellation

Low-earth orbit satellite positioning has been a research hotspot in the field of satellite navigation since it can be used as a backup positioning approach in the scene of GNSS signal occlusion and interference. However, the signal coverage of LEO satellites is small due to the low orbit altitude. In the case of limited constellation scale, it is difficult to achieve more than four-fold coverage, thus the traditional multi-satellite ranging and positioning method is not applicable. In this paper, based on the characteristics of low earth orbit satellite with fast moving speed and large Doppler frequency shift, the single satellite Doppler positioning has been proposed. And the single satellite positioning accuracy has been analyzed from the perspective of GDOP. What’s more, simulation has been made to analyze positioning accuracy versus on the satellite orbit accuracy, speed accuracy, observation period, and observation duration. The simulation results show that the single satellite positioning accuracy can converge to about 50 m in 8 min with the Doppler frequency shift observation accuracy of 1 Hz.