非平稳采样条件下宽带雷达有源干扰理论与方法研究

Noncoherent jamming can be restrained extremely by broad-band radars. Coherent jamming based on sampling and retransmitting via DRFM is the usual method against broad-band radars. High-Fidelity sampling is one of the determinants of performance of broadband radar repeater jamming. Nonstationary sampling, such as sub-Nyquist sampling and nonuniform sampling, dissatisfy the Shannon sampling theorem and may induce some unique effects. Nonstationary sampling jamming is a new hotspot in radar countermeasures while maintaining lots of advantages and unique characteristics and corresponding esearches are important in both theory and practice..In this research, the system information of active jamming based on the nonstationary sampling against broad-band radars will be founded based on the combination of the nonstationary sampling theorem and the coherent jamming.The jamming methods will also be enriched and perfected. The jamming mechanism will be explored by analying the dynamic characteristics of sampled signals. The key jamming techniques of the sub-Nyquist sampling and nonuniform sampling will be conquered. Jamming methods and applications of the nonstationary sampling will be proposed. Simulations and relevant experiments will also be taken up to verify the effect of the jamming idea. This research will give a theoretical argument and technique support for the demonstration, design and application of active jamming against broad-band radars based on the nonstationary sampling.

宽带雷达能显著抑制非相干干扰，基于DRFM的采样转发是实现宽带雷达相干干扰的重要方式。而高保真采样是宽带雷达转发干扰性能的决定因素之一。将欠采样、非均匀采样等非平稳采样方式与采样转发干扰相结合，不仅能够突破Shannon采样定理的限制，而且能够形成额外的干扰效果。非平稳采样转发干扰是雷达对抗研究的新热点，具有许多独到的特点和优越性，研究它对宽带雷达的干扰具有重要的理论和现实意义。.本项目将非平稳采样理论与相干干扰相结合，研究非平稳采样条件下宽带雷达有源干扰理论与方法，丰富并完善干扰样式：针对宽带雷达系统，分析非平稳采样信号动态特性，揭示非平稳采样干扰信号干扰机理；突破对宽带雷达欠采样干扰技术、非均匀采样干扰技术等关键技术，提出非平稳采样条件下宽带雷达有源干扰样式及应用方法，完成仿真及实验验证，评估干扰效果，为非平稳采样条件下宽带雷达有源干扰的论证、设计及其应用提供的理论和仿真支持。

基于 DRFM 的转发干扰是宽带雷达相干干扰实现的主要途径，也是新型电子干扰系统发展的主流方向。将欠采样、非均匀采样以及稀疏采样等采样技术与 DRFM 转发干扰相结合，不仅降低宽带信号高保真采样难度，还将起到额外的干扰效果，进一步丰富雷达干扰理论与方法。本项目主要研究内容包括：一、非平稳采样有源转发干扰的基本原理，主要针对ISAR有源转发干扰理论，研究欠采样和间歇采样两种方式的干扰信号理论，建立干扰信号模型，研究干扰机理；该方法能够在距离向形成多个虚假目标，目标间距和间歇采样周期程反比。二、研究了基于散射波调制的非平稳采样宽带成像雷达干扰方法，分析干扰机理和不同干扰参数下的干扰效果，可在距离向产生相同的虚假目标。三、提出一种脉冲信号非平稳采样分段有源转发干扰的方法，对干扰信号进行建模，分析干扰机理和原理，对不同参数条件的干扰效果进行分析和评估，可产生一维和二维虚假目标。四、研究了基于散射波调制的非平稳采样宽带成像雷达干扰方法，首先分析基于目标散射特性调制的干扰基本原理，进一步分析基于散射波调制的非平稳采样宽带雷达欺骗干扰方法，可产生较为真实的虚假目标。