说明：  SAR成像处理的过程是从回波数据中提取目标区域散射系数的二维分布，本质上是一个二维相关处理过程,因此最直接的处理方法是对回波进行二维匹配滤波，但其运算量很大，再加上SAR的数据率本来就高，这使得实时处难于实现。通常，可以把二维过程分解成距离向和方位向两个一维过程，Range-Dopper Algorithm（简称RD算法）
(SAR imaging process is two-dimensional distribution of the scattering coefficient of the target area extracted from the echo data, in essence, is a two-dimensional process, the most direct approach is two-dimensional matched filtering of echo, its computationalthe great plus on SAR data rate was high, which makes real-time processing is difficult to achieve. Typically, two-dimensional process can be broken down into the range and azimuth to a two-dimensional process, the Range-Dopper Algorithm. (Referred to as the RD algorithm))