一种基于状态矩阵的全天球恒星识别方法研究

Celestial Sphere Stellar Identification Method Based on Data Compression

以恒星作为观测基准来获取航天器的飞行姿态信息是现行方法中精度最高的一种方式,其中恒星识别是关键,即在恒星星表库中寻找观测恒星对应的导航恒星。研究了导航星特征库的构建和恒星识别方法,提出了一种新的基于状态矩阵的全天球恒星识别方法。首先依据探测器探测极限星等的能力筛选出适用的恒星构建标准导航星表;再基于标准导航星表和探测器探测视场角范围构建导航星特征库三角形矩阵;然后基于探测器的位置和恒星个数构建识别的恒星角距观测三角形和导航星特征库三角形矩阵对应的状态矩阵,并比较观测三角形角距和导航星特征库三角形矩阵里角距标识状态矩阵;最后基于标识的状态矩阵标志提取对应导航星特征库三角形矩阵里的角距,并与观测三角形角距匹配比较识别出观测恒星。模拟探测器的视场角为10°×10°,探测极限为6.5等星,导航星为9040颗恒星。实验结果表明,恒星识别时使用状态矩阵标识能减小匹配搜索的时间复杂度和空间复杂度,提高恒星匹配识别效率。

It is the most accurate method to obtain the attitude information of the spacecraft by using the stellar as the observation datum,and the key of this method is to identify the stellar.The stellar identification is to find a guide stellar corresponding to the observed stellar in the guide stellar catalog.In this paper,the construction of the guide stellar feature database and the stellar identification methods are studied,and a new celestial sphere stellar identification method is proposed by using data compression.Firstly,many suitable stellars are screened to construct the standard guide catalogue according to the ability of the stellar detection limit.And the lossless compression of guide stellar feature database is constructed according to the standard guide catalogue and detector field angle.Secondly,the observation triangle of angular distance of identification stellars is constructed by using the position information of detector and the number of stellars.And the stellar number and angular distance are extracted and constructed state matrix from the compression guide stellar feature database;Thirdly,by comparing the angular distance of observation triangle with the angular distance of guide stellar feature database,the identification of state matrix is marked.And the angular distance of guide stellar feature database corresponding to the identification of state matrix is extracted and is compared with the angular distance of observation triangle to identify the stellar.The field of detector is 10°×10°,the detection limit is 6.5 magnitude star,and there are 9040 guide stellar in the guide stellar catalog.The results show that this method can be reduce search time and space complexity by using the state matrix.