Multi-Area Controllable Suppression Jamming Method Against SAR Based on Two-Dimensional Phase Mismatch

Abstract

In the imaging process of SAR, the secondary phase mismatch can cause image defocusing. In this paper, a suppression jamming method against SAR based on two-dimensional (2D) phase mismatch is proposed through a designed jammer system. By extracting and resampling the intercepted radar signal through the designed jammer, the bandwidth of the linear frequency modulation (LFM) signal can be changed, which causes defocusing in the range dimension after matching filtering. Azimuth phase mismatch is achieved through velocity mismatch, which leads to azimuth defocusing after azimuth matching filtering. Efficient coverage of multiple dispersed important regions can be achieved by adjusting the parameters of jamming targets reasonably, such as modulation bandwidth, azimuth velocity, jamming positions and jamming power. Theoretical analysis is conducted on the implementation of the algorithm and its 2-D controllability in terms of jamming location and jamming area, as well as the required jamming power. The correctness of the theoretical model is verified by simulation results of spaceborne SAR. This method is quite simple to implement and can achieve efficient coverage of multiple dispersed targets, providing a basis for the implementation and application of SAR jamming in active radar responders.