基于分数阶傅里叶变换的聚束SAR成像算法

摘要

The paper focuses on high azimuth resolution imaging of a spotlight SAR. An imaging method for spotlight SAR based on fractional Fourier transform ( FRFT) is proposed in this paper with the characteristic analysis of the spotlight SAR echo signals and the principles of FRFT. The method improves azimuth focusing performance by using FRFT to process spotlight SAR azimuth signals because of the FRFT’s excellent energy focusing ability to chirp signals.Theoretical derivation and simulation are carried out to analyze the imaging performance of FRFT azimuth processing,and finally the image formed by real data illustrates feasibility and effectiveness of the spotlight SAR imaging method.%针对聚束式合成孔径雷达（ SAR）高分辨率成像的问题，在分析聚束SAR回波信号特点和阐述分数阶傅里叶变换（ FRFT）原理及性质的基础上，提出了一种基于分数阶傅里叶变换的聚束SAR成像算法，利用分数阶傅里叶变换对线性调频信号良好的能量聚集性，对聚束SAR回波信号进行方位向处理以提高方位聚焦性能，通过理论推导和仿真数据分析了FRFT方位向处理的算法成像性能，并通过实测数据成像，验证了算法的可行性和有效性。