基于铱星突发信号的导航定位技术研究

全球导航卫星系统(GNSS)存在落地信号弱、易受干扰等问题，而低轨卫星系统因其较高的信号落地功率、较低的信号空间损耗以及较好的多普勒特性逐渐成为导航领域的研究热点. 铱星星座是目前唯一已实现全球覆盖的低轨卫星系统，其提供的授时与定位(STL)能力主要服务于美国军方，具体信号体制及接收处理技术均未公开发布. 通过对铱星STL突发信号体制开展深入研究及解析，提出利用STL突发信号实现非合作导航定位，并通过实收信号完成了定位解算算法验证，实收试验结果表明所提算法能够实现精度优于100 m的定位. 研究成果能够为我国低轨导航系统建设提供理论基础，有效推进下一代卫星导航系统持续发展. 

Research on positioning technology based on Iridium burst signal

Global Navigation Satellite System (GNSS) has weak landing signal and is vulnerable to interference, etc., while low-orbit satellite system has gradually become a research hotspot in the navigation field due to its high landing power, low signal space loss and good Doppler characteristics. Iridium is the only low orbit satellite system that has achieved global coverage. Its satellite time and location(STL) capabilities are mainly for the US military. The specific signal system and processing technology have not been publicly released. Through in-depth study and analysis of Iridium STL burst signal system, this paper proposes to realize non-cooperative navigation and positioning by using STL burst signal, and completes the verification of positioning algorithm by receiving STL burst signal. The result shows that the proposed algorithm can achieve positioning accuracy better than 100 m. The research results can provide a theoretical basis for the construction of China’s low-orbit navigation system and effectively promote the sustainable development of the next generation of satellite navigation system.