基于空域极化控制的雷达导引头主瓣多点源干扰抑制技术

The battlefield electromagnetic environment faced by radar seekers is becoming complex increasingly. Especially when there are multiple targets or jamming sources in the main-lobe beam of the radar seeker, the main lobe multi-source jamming is formed, which makes the traditional radar anti-jamming methods unapplicable. Moreover, target detection and angle tracking of monopulse radar seekers based on conventional signal processing face the probability of failure. Based on the polarized monopulse angle measurement system of radar seeker, this project breaks through the traditional anti-jamming method with interference energy suppression and signal-to-noise ratio enhancement, and proposes a new anti-jamming method of spatial polarization control. In the 3 dB main-lobe of radar transmitting and receiving beams, through man-made significant changes in spatial polarization, characteristic difference between target scattering signal and multi-source interference radiation signal in spatial-polarized domain is enhanced, and the target parameters is extracted from the resulting spatial-polarized domain characteristics of multi-source, which can be used to achieve accurate target angle measurement under the condition of main-lobe multi-source interference.

雷达导引头面临的战场电磁环境日趋复杂，尤其是当导引头主瓣波束内同时存在多个目标或干扰源时，形成主瓣多点源干扰，导致传统雷达抗干扰方法难以为继，基于常规信号处理的单脉冲雷达导引头目标检测与测角跟踪面临失效威胁。本项目立足雷达导引头极化单脉冲测角体制，打破基于干扰能量抑制和信干噪比提升的传统抗干扰思路，转而提出一种新的空域极化控制抗干扰方法，在雷达发射波束与接收波束的3dB主瓣内，人为主动制造显著的空域极化变化，增强目标散射信号与多点源干扰辐射信号在空域-极化域的特性差异，并从由此产生的多点源空域-极化域特征量中提取目标参数，实现主瓣多点源干扰条件下的目标准确测角。

本项目以防空反导、精确制导等应用为背景，立足于极化单脉冲测角体制，提出空域极化控制抗干扰新思路，研究主瓣多点源干扰条件下的雷达导引头精确目标角度估计方法，突破空域变极化动态波束形成、非相干多点源干扰抑制、相干多点源干扰抑制、目标精确角度估计等关键技术，为破解雷达导引头主瓣多点源干扰对抗难题，提供创新的理论与技术支持。. 针对研究目标，本项目基于空域极化控制新概念，对主瓣多点源干扰的抑制与分辨问题展开研究。. 在接收空域极化控制方面，提出5项主瓣多点源干扰抑制与分辨关键技术，分别是：1极化空域零陷解耦滤波方法（用于极化阵列抑制主瓣干扰后的主瓣波束保型）、2极化盲源分离干扰抑制方法（基于高阶累积量约束，抑制主瓣干扰、保留目标信号）、3非相干两点源压制干扰滤波方法（用于极化单脉冲系统抑制主瓣非相干两点源压制干扰）、4极化阵列滤波后测角校正方法（用于极化阵列单脉冲系统滤波后的目标精确测角）、5极化交错子阵单脉冲双源分辨方法（用于主瓣内重叠两点源目标的分辨，适用于非矩阵天线阵列构型）。. 在发射空域极化控制方面，提出3项主瓣相干多点源干扰抑制关键技术，分别是：1空域变极化波束形成方法（用于产生发射空域变极化波束）、2基于空域变极化波束的相干多点源干扰抑制方法（用于抑制双/多源交叉眼角度诱偏干扰）、3基于发射极化控制的多径干扰抑制方法。. 通过以上8项关键技术研究，对项目研究目标形成多层次、多对象的技术支撑，为破解雷达导引头主瓣多点源干扰对抗难题提供了新的解决方案。