Abstract:Comprehensive performance analysis and comparison of four global satellite navigation systems (GNSS) have been lacking for polar regions. Based on the precise ephemeris, the visibility and positioning accuracy of current constellations in the polar region was analyzed via the route-point selection and region analysis. Subsequently, its performance was compared to solve that the overall analysis was scarcely involved in the existing reference. Moreover, the problem that the point-analysis cannot represent the integrated performance in the polar region was settled, and the theory-based principle was offered for the application and development of the polar GNSS. The results demonstrated that, without the consideration of the disturbance of the external electromagnetic, the positioning accuracy of GLONASS was worse than the other three satellite systems. However, these four systems have already covered the polar region well, satisfying the fundamental requirement of polar positioning. Conclusively, the research direction on polar GNSS tends to eliminate the impairment of the harsh electromagnetic environment.