关键词: 全球覆盖, 低轨卫星, 导航增强, 星座设计

Abstract: A constellation design method of LEO (Low Earth Orbit) satellites augmentedconstellation for navigation is presented since global LEO satellites becoming a hot spot. Firstly, the relationship between the orbit altitude and the visible spherical crown is deduced, thus the constellation altitude can be computed with the space debris distribution, economy and collision risk. Then, the relationship between the elevation and the orbit inclination is derived, and meanwhile the constellation inclination is determined to get north and south poles coverage. Next, compared with Iridium, it is demonstrated that a single constellation can′t achieve a uniform visible satellites distribution and DOP（Dilution of Precision）on global scale. Finally, an LEO satellites constellation design method is proposed, which can achieve global coverage while make the DOP (Dilution of Precision) and the visible satellites distribute evenly around the world. The results show that the mixed constellation designed by the method can achieve a global coverage and even distribution of visible satellite numbers and DOP.

Key words: global coverage, LEO satellites, navigation augmentation, constellation design