摘要
针对硬X射线巡天望远镜具有的18个探测器的设计,本文给出了直接解调成像方法快速实现的两个途径。一是根据点扩展函数值中有大量零元的事实,给出了基于点扩展函数值的非零元的Lucy迭代计算和存储方法;二是将直接解调成像方法中Lucy迭代改为观测数据按一定方式分组排序的Lucy迭代。数据实验表明,本文方法大幅度提高了直接解调成像的速度。
According to the design in which there are 18 detectors in Hard X-ray Modulation Telescope system of astronomical satellite, the authors propose two ways to fast implementation of the direct demodulation imaging method. One is calculation and storage method for Lucy iteration based on nonzero elements of point spread function of detector collimator, according to the fact that there are a large number of zero elements in point spread function. The other is to substitute Lucy iteration on the ordered subsets of observed data for Lucy iteration on all data in the direct demodulation imaging method. The numerical experiment results show that the imaging convergent speed of the direct demodulation imaging method is accelerated dramatically using the ways proposed in the present paper.
出处
《CT理论与应用研究(中英文)》
2005年第1期17-23,共7页
Computerized Tomography Theory and Applications
基金
国家重点基础研究计划(G 20000776)资助。
关键词
直接解调成像方法
硬X射线巡天望远镜
Lucy迭代
分细Lucy迭代
点扩展函数
direct demodulation imaging method, hard x-ray modulation telescope (HXMT) ,lucy iteration, order subset Lucy iteration, point spread function