A Novel Wavenumber Domain SAR Imaging Algorithm Based on the Fractional Fourier Transform  

作　　者：XU Huaping XIAO Zhongyuan GAO Jing LI Chunsheng 

机构地区：[1]Department of Electronic and Information Engineering, Beihang University

出　　处：《Chinese Journal of Electronics》2014年第4期866-870,共5页电子学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(No.60901055)

摘　　要：The conventional Wavenumber domain algorithm(WDA) employs Fast Fourier transform(FFT) to implement matched filter. It is characterized by its high precision SAR imaging. Compared with FFT, Fractional Fourier transform(Fr FT) can provide lower and narrower sidelobes when it is applied to compress chirp signals at the optimal transform. This paper proposed a novel SAR imaging algorithm, termed Fr WDA which replaces FFT in WDA with Fr FT. The Fr WDA was derived and its implementation was presented. How to choose the optimal transformation order was given subsequently. The Fr WDA preserves high precision focusing, and has better performance on sidelobe suppression. The Fr WDA is more suitable for the high precision SAR imaging, especially in target detection and recognition. Simulation results demonstrate that Fr WDA provides better performance on focusing and sidelobe suppression compared with the classical FFT-based WDA.The conventional Wavenumber domain algorithm （WDA） employs Fast Fourier transform （FFT） to implement matched filter. It is characterized by its high precision SAR imaging. Compared with FFT, Fractional Fourier transform （FrFT） can provide lower and narrower sidelobes when it is applied to compress chirp signals at the optimal transform. This paper proposed a novel SAR imaging algorithm, termed FrWDA which replaces FFT in WDA with FrFT. The FrWDA was derived and its implementation was presented. How to choose the optimal transformation order was given subsequently. The FrWDA preserves high precision focusing, and has better performance on sidelobe suppression. The FrWDA is more suitable for the high precision SAR imaging, especially in target detection and recognition. Simulation results demonstrate that FrWDA provides better performance on focusing and sidelobe suppression compared with the classical FFT-based WDA.

关 键 词：SAR imaging Wavenumber domain algorithm FFT Fractional Fourier transform sidelobe suppression. 

分 类 号：TN957.52[电子电信—信号与信息处理]