星间链路构型对自主导航精度的影响分析

摘要

以北斗仿真星座为对象,探讨UHF波段与Ka波段的不同星间链路建链条件下GEO、IGSO及MEO卫星的可见链路数及PDOP值的变化.此外,还针对不同星间链路构型方案,分别采用其对应仿真观测数据进行60 d自主导航解算,通过对解算结果精度的分析,探讨星间链路测距模式及星间链路构型对自主导航的影响.结果显示,星间链路测距模式对自主导航精度无影响,而星间链路构型则对自主导航精度存在cm量级的影响.在星间链路设计过程中应综合考虑导航精度、链路负荷及建设成本等因素,以达到最优效果.%This paper has discussed the change of cross-links' numbers and PDOP values for the GEO,IGSO and MEO in the cases of different schemes by UHF signal and Ka signal aimed at the simulated constellation of BDS.Besides,some different cases of cross-link schemes have been designed.Using these simulated observations 60 days' auto-navigation has been performed.The influence of the crosslink ranging mode and the cross-link configuration to the precision of auto-navigation has been analyzed.The results indicate that the corss-link ranging mode will not affect the precision of auto-navigation.But the cross-link configuration will influence the precision of auto-navigation in the order of centimeter.Therefore,while designing the inter-satellite cross-link,navigation's precision,link's load and construction cost should be considered in order to achieve the best result.