亮星辅助下基于坐标转换的快速星图识别方法

数字天顶仪作为一种地面使用的星敏感器，主要用于高精度定位。为提高仪器的工作效率需要对星图识别的快速性进行研究。通过对恒星像点理论坐标与图像坐标的分析，构建坐标转换模型。依据星表中恒星的分布及星等筛选出视场范围内的亮星，并构建导航星表。结合导航星表完成3颗亮星的准确识别，在识别亮星的基础上解算坐标转换模型的参数。通过构建的坐标转换模型对视场范围内的恒星进行坐标转换，将转换后的星点坐标与提取的星点图像坐标进行匹配完成星图的识别，这样能够提高星图识别的快速性。实验数据表明：在保证识别星点数量的基础上，采用亮星辅助下基于坐标转换的星图识别方法使时间缩短为改进三角形星图识别算法的五分之一。

Fast star identification based on coordinate transformation assisted by bright stars

Digital zenith camera as a star sensor is mainly used for high precision positioning on the ground. To improve the correctness and rapidity of star identification, the image coordinates of star points are first analyzed, and the coordinate transformation model is established. Then the bright stars in the field of view are selected to construct the navigation catalogue. Three bright stars are identified by the triangular star identification algorithm. The coordinate transformation parameters are calculated using the three bright stars, whose correctness is checked in the meantime. Transformation of the star image coordinates is performed based on the coordinate transformation model, followed by the matching of the transformed coordinates with the star image coordinates to identify the stars. The experimental data shows that this method can effectively reduce the identification time.