天文光谱仪非完整光斑导星定位算法

Non-integral speckle star positioning algorithm for astronomical spectrometer

该文提出一种用于Tip/tilt导星跟踪校正系统的非完整光斑导星定位算法,解决常规导星定位算法无法满足天文光谱仪IMSP系统需求的问题。该算法结合图像预处理和目标星斑识别算法提取出包含目标光斑的感兴趣区域,基于峰值定位法选取非完整光斑中的一部分子图作为模板图,并利用归一化互相关法从完整光斑中找出与模板图匹配度最高的子图,根据匹配度最高的子图与模板图的相对位置以及完整光斑导星定位坐标实现非完整导星定位坐标的获取。实验结果表明:该算法的X轴方向绝对误差为0.29 px,Y轴方向绝对误差为0.02 px,平均处理时间为21.4 ms,满足IMSP系统的时效、精度和稳定性要求。

This paper proposes a non-complete speckle star positioning algorithm for the Tip/tilt star tracking and correction system,which solves the problem that conventional star positioning algorithms cannot meet the requirements of the IMSP system of the astronomical spectrometer.The algorithm combines image preprocessing and target speckle recognition algorithm to extract the region of interest containing the target speckle.Based on the peak positioning method,a part of the subgraph in the non-complete speckle is selected as the template graph,and the normalized cross-correlation method is used to find the subgraph in the complete speckle with the highest matching degree with the template graph.The non-complete star position coordinates are obtained based on the relative position between the subgraph with the highest matching degree and the template graph,as well as the coordinates of the complete speckle star positioning.Experimental results show that the algorithm has an absolute error of 0.29 px in the X-direction and 0.02 px in the Y-direction of the star positioning coordinates,with an average processing time of 21.4 ms,which meets the requirements of the IMSP system in terms of efficiency,accuracy and stability.