摘要
提出了一种基于空时自适应处理(STAP)杂波抑制和修正的离散Chirp-Fourier变换(MDCFT)参数估计的双天线合成孔径雷达(SAR)运动目标检测和成像方法。将MDCFT变换应用于经过STAP杂波抑制后的信号,在MDCFT幅值平面内同时完成对运动目标的检测和多普勒参数的估计。分析了STAP方法对SAR回波的滤波效果,建立了适合SAR系统的MDCFT模型。在分数阶傅里叶域进行滤波以消除杂波对相位的影响,进而利用通道间的相位差和多普勒中心频率对运动目标准确定位并估计径向速度。通过大量的仿真实验验证了该方法的正确性。
The paper presents a dual-channel SAR moving-target imaging method via clutter suppressing by space-time adaptive processing (STAP) and parameter estimating by modified discrete Chirp-Fourier transform (MDCFT). The MDCFT is used to handle the output signals of STAP, and the detection and parameter estima- tion can be solved simultaneously in the MDCFT amplitude plane. An analysis is made about the filtering effect of STAP on the SAR receive signals. The MDCFT model fitted for SAR systems is established. Filtering in the fractional Fourier domain eliminates the phase error caused by the clutter. After then, the exact position and the radial velocity of the moving target are estimated via the channel phase difference and the Doppler center frequency. Simulation results prove that the method is effective and correct.
出处
《系统工程与电子技术》
EI
CSCD
北大核心
2009年第2期342-346,共5页
Systems Engineering and Electronics