前视SAR压缩感知成像算法

Forward Looking SAR Imaging Algorithm via Compressive Sensing

以进一步提高前视SAR成像的分辨率为目的,提出了一种基于压缩感知的前视SAR成像算法。前视SAR是一种可以实现对飞行路线正前方的区域进行成像的工作模式,通过分析德国宇航局提出的前视SAR系统——视景增强的新型区域成像雷达(SIREV)可知,由于SIREV系统天线长度的限制,使得等效的合成孔径长度较短,从而导致成像的分辨率较低。而基于压缩感知的前视SAR成像算法可以在方位向等效得到一个较长的虚拟天线,因此可以在同样长度天线的情况下获得更高的成像分辨率。仿真结果表明,该方法可以实现对点目标、分布目标和面目标的成像,并且提高了成像的分辨率。

For the purpose of obtaining high-resolution imaging of forward looking SAR,this paper proposed a forward looking imaging algorithm based on the theory of compressive sensing（CS）.Forward looking SAR was a new operational mode for imaging the frontal targets of the flight path.Firstly,we analyzed the theory of sector imaging radar for enhanced vision（SIREV） put forward by the German Space Agency.It was concluded that the imaging resolution was limited by the short synthetic aperture which resulted from the short antenna.Then,a forward looking SAR imaging algorithm based on compressive sensing was proposed.The filter functions of the algorithm were constructed in the time domain and these functions were independent of the target number and Doppler frequency.This algorithm can achieve higher imaging resolution in the same case with the system of German Space Agency.The simulation results show that the proposed method can achieve imaging of point target,distribution target and area target,and higher resolution images can be obtained.