航空学报 > 2002, Vol. 23 Issue (1): 33-37

利用分数阶Fourier域滤波的机载SAR多运动目标检测

孙泓波, 顾红, 苏卫民, 刘国岁   

  1. 南京理工大学电子工程技术研究中心 江苏南京 210094
  • 收稿日期:2000-12-12 修回日期:2001-02-15 出版日期:2002-02-25 发布日期:2002-02-25

USING THE FILTERING IN FRACTIONAL FOURIER DOMAIN FOR AIRBORNE SAR MULTIPLE MOVING TARGETS DETECTION

SUN Hong-bo, GU Hong, SU Wei-min, LIU Guo-sui   

  1. Research Center of Electronic Engineering Technology, Nanjing University of Science and Technology, Nanjing 210094, China
  • Received:2000-12-12 Revised:2001-02-15 Online:2002-02-25 Published:2002-02-25

摘要:

强度相差较大的多运动目标检测是机载合成孔径雷达 ( SAR)技术的一个重点和难点,传统的频域滤波和现代的时频分布方法都无法解决这个问题。首先分析了机载 SAR运动目标回波本质上为线性调频信号,据此提出一种基于分数阶 Fourier域滤波的运动目标检测新方法,并且应用逐次消去的思想有效地解决了强度相差较大的多目标检测问题。仿真的结果验证了算法的有效性。

关键词: 分数阶Fourier变换, 合成孔径雷达, 运动目标检测, 线性调频信号, 滤波

Abstract:

The detection of multiple moving targets whose scattering intensities differ evidently is difficult but important in airborne synthetic aperture radar (SAR) techniques. The traditional filtering method in the frequency domain and the modern time frequency distribution technique can't achieve this purpose. In this paper, it is analyzed that the echo of a moving target is a chirp signal naturally. Thus, a new technique of SAR moving target detection based on fractional Fourier transform is proposed. By eliminating large targets one by one in the fractional Fourier domain, the small targets can be detected effectiveness. The simulation results prove the effectiveness of this technique.

Key words: fractional Fourier transform, synthetic aperture radar, moving target detection, linear frequencymodulation signal, filtering