星载SAR全方位模糊特性及计算方法

常规的星载SAR模糊度计算方法是基于距离向一维方向图和方位向一维方向图,独立进行距离向模糊度和方位向模糊度分析.由于星载SAR对地观测是二维的,因此距离模糊度是全方位的,且真实的模糊能量仅来自于距离向模糊信号,方位向模糊是基于距离向模糊信号的基础上由于成像处理导致的模糊信号重组.为解决系统设计时预估分析的距离向模糊度值...

Research on omnidirectional ambiguity characteristics and calculation method of spaceborne SAR

The conventional ambiguity calculation method of spaceborne SAR is based on range one-dimensional pattern and azimuth one-dimensional pattern, and the range ambiguity and azimuth ambiguity are analyzed independently. However, the azimuth ambiguity is based on range ambiguity signal, which is caused by image processing. In order to solve the problem that the estimated range ambiguity value in system design is inconsistent with the actual imaging effect and to restore the essence of azimuth ambiguity, a new method of ambiguity analysis and calculation for spaceborne SAR was proposed. Firstly, the causes of range and azimuth ambiguity and the relationship between them were analyzed. Then, the range conversion model between the arbitrary pointing angle of the pattern and the actual observation to the earth was established. At the same time, based on the two dimensional pattern, the calculation method and steps of the omnidirectional ambiguity were given. Finally, the simulation design was carried out and the results show that the omnidirectional ambiguity calculation method is more in line with the actual imaging effect, providing a reference for the subsequent high-resolution spaceborne SAR system design and ambiguity suppression.