精细导星星库是空间大口径望远镜开展导星过程的必要组成部分, 是用来确定空间望远镜视轴绝对指向的关键依据。基础星表的挑选、导星星库的容量、划分方式和天区搜索速度对于实现精细导星功能和性能指标都极为重要。在视场约为0.08 deg2精度要求高的条件下, 选用UCAC4星表作为基础星表, 提出混合分区星等过滤算法进行导星筛选, 为了实现星表的快速搜索, 对导星星表的存取方式进行了详细分析, 构建了一个由约400万颗10 mv~16 mv导星组成的精细导星星库, 并进行星库均匀性和搜索速度分析。仿真结果表明, 基于UCAC4星表构建的16 mv精细导星星库全局均匀性达到0.44, 导星搜索时间0.05 s, 视场中星数适中, 能被高效识别的概率达到75.51%, 可作为精细导星星图识别的基准, 支撑未来大口径空间望远镜的观测。

As necessary part of guiding process carried by large space telescope, fine guidance star catalog is key basis to determine absolute pointing of LOS of spacecraft telescope. Selection of guide stars, catalog based storage capacity, division and regional search speeds are vital to realize functions and performances of fine guidance sensor. Under conditions of FOV about 0.08deg2 and high precision requirements, UCAC4 is selected as basic star catalog, and mixed partition visual magnitude filtering algorithm is proposed to select guide stars. In order to realize fast searching of catalog, guide star table access mode is analyzed in details; 10 mv~16 mv fine guidance star catalog, containing about 4 million stars, is constructed to analyze star catalog uniformity and search speed. Simulation results show that global uniformity of 16 mv fine guidance star catalog based on UCAC4 reaches 0.44, and star search speed reach 0.05 s. Stars number in FOV is moderate and efficiently identified probability reaches 75.51%. This star catalog can be used as basis of fine guidance star map identification to support large-aperture space telescope observations.