顺轨三频三孔径星载SAR的运动目标检测及定位方法研究

杂波背景下，传统的多通道SAR运动目标检测方法在杂波对消后即实施目标检测，并不考虑目标的距离徙动校正，这种做法会丢失某些快速目标，虽能够检测到速度不是特别快的目标，却可能存在测速模糊，难以对其准确定位。对此，该文提出用3频3孔径SAR解决杂波对消后快速目标的多普勒模糊问题，并用双频共轭处理(DFCP)和Keystone变换对动目标解多普勒模糊、进行距离徙动校正，提高信噪比，进而实现对目标的检测、无模糊测速和定位。该方法在可获得与其他方法相当定位精度的同时，扩大了可检测和定位的目标的速度范围。仿真结果证明了该文方法的有效性。

Research on the Method of Moving Target Detection and Location with Three-Frequency Three-Aperture Along-Track Spaceborne SAR

In the case of clutter, conventional multi-channel SAR (Synthetic Aperture Radar) executes moving target detection immediately after clutter cancellation, and the influence of range migration is ignored. However, this approach may lose some fast target. The target that not so fast can be detected, but the estimated velocity may be ambiguous, and target accurate location becomes even difficult. So three-frequency three-aperture SAR is presented in this paper to remove the Doppler ambiguity of fast target after clutter suppression. Dual Frequency Conjugated Processing (DFCP) and Keystone transform are employed to remove the Doppler ambiguity and correct range migration of moving target. Thus the Signal Noise Ratio (SNR) can be improved, and then target detection, velocity estimation and location without ambiguity can be completed. The proposed method can achieve the same location accuracy with the existing method as well as increase greatly the velocity range of fast target that can be detected and located. The simulation results show the effectiveness of proposed method.