由空间频域上的非均匀采样数据重建图象的方法研究

STUDY ON THE METHOD OF RECONSTRUCTING IMAGE FROM THE UNEVENLY SPACED DATA IN THE SPATIAL FREQUENCY DOMAIN

本文深入研究了由空间频域上的非均匀采样数据重建图象的“双线性插值加二维快速傅里叶反变换”方法。它的基本思想是首先确定一个均匀的栅网,然后应用双线性插值将给定的非均匀采样数据插到这一栅网的各个结点上,再对结点上的数据应用二维快速傅里叶反变换。本文提出了确定栅网的原则,讨论了双线性插值,并分析了关于二维快速傅里叶反变换的一些重要问题。将这种方法应用于合成孔径雷达(SAR)的成象处理中,得到了满意的结果。

This paper studies intensively the 'bilinear interpolation and 2D-IFFT' method of reconstructing image from the unevenly spaced data in the spatial frequency domain. The basic ideas are to decide an evenly grid, interpolate the unevenly spaced data on a uniform grid and take the 2D-IFFT of the data on the uniform grid. The paper presents the principle of deciding the grid, discusses bilinear interpolation and analyses some important problems of 2D-IFFT. The method has been applied to synthetic aperture radar(SAR) imaging and the result is satisfactory.