基于地月L2点中继星的月球背面目标定位误差分析

Analysis of Target Location Errors at Far Side of Moon based on Earth-Moon L2 Satellite

针对用于实现月背定位的地月L2点中继星研究对L2点定位误差分析的需求,首先建立了基于地月L2点的单星、双星、三星无源以及三星有源这四种定位体制的数学模型,然后在月固坐标系下,针对定轨误差和星间时钟误差这两种误差来源,计算了四种定位体制下的定位误差。以星历数据为基础进行了仿真,分别定量评估了四种定位模式的定轨误差和星间时钟误差对着陆器定位精度造成的影响。结果表明,上述四种定位体制的定位误差都随着定轨误差的增加而增加,且三星有源定位精度最优。此外三星无源的定位精度会受到星间时钟误差的影响。

To satisfy the demand of target positioning at the far side of the Moon based on Earth-Moon L2 Satellite, the target positioning errors of Earth-Moon L2 were analyzed. First, four positio-ning schemes based on the earth-moon L2 point were investigated including the single satellitescheme, dual-satellite scheme, tri-satellite passive scheme and tri-satellite active scheme. In the lu-nar fixed coordinate system, the positioning error of the four schemes were analyzed according to theorbit error and inter satellite clock error. The exported ephemerides were used to evaluate the posi-tioning precision quantitatively. Four schemes were provided in this paper for the positioning of thelunar lander on the far side of the moon or on the Antarctic and the positioning accuracy of theseschemes were analyzed. The simulation results showed that the positioning error increased with theorbit error; the tri-satellite active scheme had the best accuracy; and the accuracy of tri-satellitepassive scheme was influenced by inter satellite clock error.