天文像复原迭代位移叠加法中初始信息的选择  

The Selection of Initial Information in Iterative Shift-and-AddTechnique for Astronomical Image Reconstruction

作　　者：邱耀辉[1] 刘忠[1] 卢汝为[1] 楼柯[1] 

机构地区：[1]中国科学院国家天文台云南天文台,光学天文联合开放研究实验室,云南昆明650011

出　　处：《云南天文台台刊》2002年第4期29-36,共8页Publications of the Yunnan Observatoty

基　　金：国家自然科学基金资助项目(19873017);中科院天文口基金资助.

摘　　要：给出了天文像复原"迭代位移叠加法"的第一步中确定位移基准点的方法—将目标像结构的初始信息与目标斑点图间的互相关运算的极大值点作为基准点。按此基准点对目标斑点图进行位移叠加,第一步中初始信息的选择是展开迭代位移叠加过程的关键。讨论了目标初始信息的性质和提取方法。On the principle of 'iterative shift-and-add technique' for astronomical image reconstruction,a proper datum point for shifting and adding the speckle images of an observed object can be determined by an iterative process in some methods.One of these methods is the correlation algorithm of information of the object image structure with the speckle images,then the maximum value point of the cross correlation can be used for a proper datum point.In the iterative shift-and-add technique,How to select the initial information in the first step is the key to open the process of the iterative shift-and-add.The character of the initial information of the object and a method to pick up the information are discussed.After giving the basic definition of the iterative shift-and-add technique which proposed by us recently,the mathematics model of an object image described by δ function is posed.In view of the model,three conditions which should be satisfied with by initial information of the object image structure are pointed.1).The initial information should be composed by discrete point sources described by δ function.2).The geometric distribution of the points of initial information should be equal to the geometric structutre of a certain part of the object image.3).The intensity of every point source of initial information can be all same value.The most important character of initial information is that it must contain information of the structure of the object image,because the fact that the maximum value point of the cross correlation between informaion and the speckle images of the object will determine the position of the maximun strong diffraction limited image of the object hid in the speckles of every speckle image.Following the character of the initial information some methods for taking the initial information are got.The different methods will be used for different objects.For example,if an object image has only one outstanding bright point source,because this piont source will produce the

关 键 词：天文像复原 迭代位移叠加法 初始信息 相关运算 天文望远镜 

分 类 号：P111.2[天文地球—天文学]