机载相控阵雷达灵巧干扰信号模型及抑制方法研究0

目前对灵巧干扰的研究主要集中在常规地面雷达,对于机载雷达下的干扰模型及其抑制方法的研究较少。针对此种情况,建立了机载雷达背景下噪声卷积干扰、随机移频干扰和延时转发干扰3种典型灵巧干扰的空时信号模型,并从杂波自由度、空时功率谱图和距离-多普勒谱图的角度分析了干扰分布特性以及影响空时自适应处理(space-time adaptive processing, STAP)性能的内在机理,在此基础上提出了一种基于单元平均选小检测的机载雷达杂波和干扰同时抑制方法。该方法从杂波空时功率谱角度准确估计干扰来向,并据此形成干扰辅助波束,最后通过STAP实现干扰和杂波的有效抑制。仿真结果表明,所提方法相对于传统级联抑制方法,对延时转发灵巧干扰的抑制性能改善5 dB以上,验证了所提方法的有效性。

Research on smart jamming signal model and suppression method for airborne phased array radar

At present, the research on smart jamming mainly focuses on conventional ground radar, there are few studies on the jamming model and its suppression method under airborne radar. The space-time signal models of three typical smart jammings including noise convolution jamming, random frequency-shift jamming and time-delay repeater jamming under the background of airborne radar are established. Then, the distribution characteristics and the internal mechanism that affects the performance of space-time adaptive processing (STAP) are analyzed from the perspectives of clutter freedom degrees, space-time power spectrum and range-Doppler spectrum. On this basis, a simultaneous clutter and jamming suppression method for airborne radar based on the smallest of cell average detection is proposed. The method accurately estimates the jamming direction from the perspective of clutter space-time power spectrum and forms an jamming auxiliary beam accordingly. Finally, the effective suppression of jamming and clutter is achieved through STAP. The simulation results show that compared with the traditional cascade suppression method, the proposed method improves the suppression performance of time-delay repeater smart jamming by more than 5 dB, which verifies the effectiveness of the proposed method.