快速全天自主星图识别算法的研究

三角形识别算法是工程应用中较为成熟的算法，为了克服三角形因特征维数较低带来的冗余匹配问题，提出了一种改进的三角形算法。由于经过标定后观测星之间的相对星等差比较稳定，增加星等差作为辅助识别特征，同时，引入三角形以外的第四颗星为顶点，与三角形构成假想的四面体，顶点与底面三角形三个点的角距既是识别特征量，也可用于检验识别的结果是否正确。为了减小导航特征库的容量及对其遍历比较带来的时间开销，对导航特征库存储内容进行了精简，并利用数据结构中的散列查找法对识别特征构造散列函数，加快了识别过程。仿真实验结果表明，该识别算法具有较快的识别时间和较高的识别率。

Reseach on fast all-sky autonomous star identification algorithm

Triangle star identification is a mature algorithm in engineering, to overcome the low character dimensions and high percentage of redundant matches, proposed an improved star identification base on traditional triangle identification algorithm. The relative magnitude information of star pair is stable and taken as assistant character during identification process. Introduced the fourth star besides triangle stars, the accessorial angular distance between them could be supplementary character to reduce redundant, and also could be verification. Appropriate characters were chosen to decrease the capacity of guide star database. In order to decrease the time spent during star-pair matching, hashing search used. The simulation result demonstrated all these improved identification efficiency and identification time reduced.