SAR时变密集干扰的张量机理及其快速自适应对抗方法研究

As a wideband active remote sensing radar, in an increasingly complex electromagnetic environment, synthetic aperture radar (SAR) is easily affected by multi-style, continuous, and time-varying complicated interferences from other electromagnetic signals in its operating frequency band. Nowadays, SAR interference suppression approaches lack of accurate modeling of these electromagnetic interferences, and it is difficult to design a fast adaptive intelligent method for suppressing the interferences. This project will aim at the deep common mechanism analysis of complex electromagnetic interference and its unified confrontation algorithm under SAR systems, which mainly includes three aspects: First, by analyzing the low-dimensional signal model of single-type isolated interference, the tensor mechanism characteristics of the continuous narrowband and wideband interferences and its difference with the real signal are deeply explored, and the high-dimensional tensor model of continuous complex interferences is accurately established; Second, analyze the tensor signal model essence to reduce the tensor model scale, and based on the tensor algebra calculation theory to strictly derive the tensor factor decomposition, and then design a fast algorithm to simultaneously suppress the multi-style continuous interference; Third, according to the time-varying characteristics of the actual complex electromagnetic environment with the platform motion and changes of observation scenes, the adaptive processing technology simultaneously against time-varying continuous interferences is studied. This project aims to build a theoretical framework for signal processing against complex electromagnetic interferences and provide important technical support for enhancing the information acquisition and sensing capabilities of SAR systems.

作为一种宽带有源遥感雷达，在日益复杂的电磁环境中，合成孔径雷达（SAR）极易受到其工作频段内其他多样式、密集、时变复杂电磁信号的干扰。目前SAR抗干扰技术缺乏对这些复杂电磁干扰的精确建模，难以设计快速自适应的智能化对抗方法，本项目将瞄准SAR体制复杂电磁干扰的深层次共性机理分析和统一对抗算法，主要包括三个方面：首先，分析单一类型孤立干扰的低维信号模型，深入探索窄、宽带多样式密集干扰的张量机理特征及其与真实信号的差异，准确建立密集复杂干扰的高维张量模型；其次，分析张量信号模型本质来降低张量模型规模，同时基于张量代数计算理论来严格推导张量因子分解，设计统一对抗多样式密集干扰的快速算法；最后，针对实际复杂电磁环境随平台运动和观测场景变化而时变的特性，研究统一对抗时变密集干扰的自适应处理技术。本项目旨在构建对抗复杂电磁干扰的信号处理理论框架，为增强SAR系统信息获取和感知能力提供重要的技术支撑。

当前电磁环境日益复杂，SAR系统在工作中很容易受到环境内敌方干扰源、无线通信信号、广播电视信号以及其他雷达信号等多样式、密集复杂电磁干扰的影响。本项目从电磁干扰时频域物理特征着手，并将其特征规律推广到高维张量空间，开发了一系列干扰抑制能力强、计算效率高的对抗干扰方法。大量地在高分3号，哨兵一号等SAR系统的实测数据上进行实验，验证了项目中开发的干扰对抗算法的有效性。经过对SAR系统干扰信号的大量研究分析，本项目首次将张量分解模型应用到SAR干扰抑制上，为以后军用和民用设备去除干扰提供了可靠的研究基础。