地形表面反射强度的数学层析成像方法  

A Mathematical Reconstruction Method of Reflectivity Function on A Circuit Terrain Surface

作　　者：吴一刚[1] 

机构地区：[1]北京信息工程学院计算机科学与工程系

出　　处：《CT理论与应用研究（中英文）》1997年第3期19-25,共7页Computerized Tomography Theory and Applications

摘　　要：若二维ＲＦ窄波反射函数是定义在地面一圆形区域内部的，并假定该圆域表面介质是弱反射介质，那么在给定时刻，接收发射器（如机载合成孔径雷达）所接收到的返回数据可视为过该圆域的一圆弧上的线积分值，Ｍｕｎｓｏｎ，ｅｔａｌ．在假定圆域半径与接收发射器运动路径到该圆域中心的距离相比很小的情况下，用直线上的线积分值来代替圆弧线上的线积分值，利用古典的Ｒａｄｏｎ变换方法，给出了该圆域反射函数的成像模式。本文将克服这一限制，利用广义Ｒａｄｏｎ变换的反演结果，在Ｍｕｎｓｏｎｅｔａｌ工作的基础上，给出了该反射函数的层析成像级数表达式，从而在数学上推广了他们的工作，为重建地形表面反射函数提供了一种方法，并为利用层析成像理论解释雷达成像中的问题提供了一个新的途径。If a narrow RF wave is emited into a two dimentional weakly reflecting medium in a circular domain on the terrain from a source receiver which moves along a line over the domain, the resulting echo data that the source receiver receives urder spotlight mode SAR can be regarded as a line integral value of the reflectivity function along a segment of arc through the domaim at a given time. Supposing that compared with the distance of the trace line along which the source receiver moves to the center of the circular domain, the radium of the circular domain is very small, Munson etal regarded the line integral values along arc throngh the domain as the line integral values along lines through the domain and gave out the formula for reconstructing the reflectivity function by using classical Radon transform. Based on the work of manson etal, this paper will give out the formula for reconstructing the reflectivity function first by converting the resulting echo data into the line integral values along circles through the domain and then by using Generalized Radon transform over circles through the domain and improve the work of Munson etal, and provide a way in which the terrain reflectivity function is reconstructed.

关 键 词：合成孔径雷达 层析成像 地形表面 反射强度 

分 类 号：P631.325[天文地球—地质矿产勘探]