【作者】 于春锐；

【导师】 梁甸农；

【作者基本信息】 国防科学技术大学 ， 信息与通信工程， 2012， 博士

【摘要】 合成孔径雷达（SAR）作为一种主动式微波成像雷达，具有全天候、全天时和远距离成像的特点，已广泛应用于资源勘察、环境监测、灾害预警和军事侦察等领域。采用多个接收天线的多通道SAR，具有许多单通道SAR无法比拟的能力：干涉测高、高分辨率、宽测绘带、杂波抑制、抗干扰等。在复杂电磁环境中，SAR系统的信息获取能力将会大大降低。合成孔径雷达有源干扰抑制技术，作为保证SAR系统的高可用性的关键问题，具有重要的现实意义和军事需求。论文针对合成孔径雷达有源干扰抑制问题，从SAR射频干扰抑制技术、多通道SAR有源压制干扰抑制技术、多通道SAR有源欺骗干扰抑制技术、SAR有源干扰抑制效果评估四个方面开展研究。第一章为绪论，阐述了论文的研究背景和意义，分析了SAR技术、SAR干扰技术和SAR有源干扰抑制技术的研究现状，并简要介绍了论文的研究工作。第二章研究了SAR射频干扰抑制技术。首先建立了RFI环境下的SAR信号模型，提出了三种RFI抑制方法：一是基于频域双陷波器的RFI抑制方法，该方法同时对接收信号和匹配滤波器进行相同的陷波处理，可以补偿相关函数峰值的损失，提高了干扰抑制性能；二是基于CEMD的自适应滤波RFI抑制方法，该方法对包含RFI的回波进行初步CEMD分解，估计出回波中RFI分量，并将其做为自适应滤波器的参考信号，取得了良好的干扰抑制效果；三是基于奇异值分解的RFI抑制方法，该方法通过对观测数据矩阵进行奇异值分解，根据奇异值分布构造干扰子空间和信号子空间，利用二者的正交性可以有效的抑制RFI信号，且尽可能保留目标回波信号。第三章研究了基于多通道SAR体制的有源压制干扰抑制技术。首先分析了有源压制干扰的实现机理，将有源压制干扰信号分为直达波压制干扰和散射波干扰，建立了有源压制干扰环境下的多通道SAR信号模型；针对直达波压制干扰，研究了基于慢时间STAP的直达波压制干扰抑制方法；针对散射波压制干扰，研究了基于快时间STAP的散射波压制干扰抑制方法。第四章研究了基于多通道SAR体制的有源欺骗干扰抑制技术。详细分析了有源欺骗干扰的实现机理，根据实现方法的不同，将有源欺骗干扰信号分为直达波欺骗干扰和散射波欺骗干扰；针对直达波欺骗干扰，研究了基于慢时间STAP的直达波欺骗干扰抑制方法；针对散射波欺骗干扰，研究了基于快时间STAP与脉冲分集相结合的干扰抑制方法。第五章研究了SAR有源干扰抑制效果评估技术。针对有源压制干扰抑制效果评估，研究了相应的主观评估方法和客观评估方法，提出了基于图像质量等级评估标准的主观评估法、基于回波能量的客观评估方法和基于图像质量指标的客观评估方法；针对有源欺骗干扰抑制效果评估，研究了基于图像相关系数的客观评估方法和基于欧几里德空间距离的客观评估方法。第六章为结论与展望，总结了论文的主要工作和创新点，并对下一步工作进行展望。更多还原

【Abstract】 Synthetic ApertureRadar (SAR) is a special type of active microwave sensor. Withthe ability of generating fineresolution images from long stand off ranges, either day ornight,SAR has got a wide range of applications and plays an important role in earthobservation, environment monitor, disaster predication and military reconnaissancefields.The use of multiple antennasfor SAR is referred to as multichannel SAR andoffers the additional abilities to perform heightestimation of the ground, improve theresolution, providewide swathand suppress backscatter and/or undesiredinterferences.The informationacquisitioncapability of SAR will reduce greatly in thecomplicated electromagnetic envirnoment. SAR ECCM is a key factor in the reliabilityofSAR system. With the SAR ECCM as the background, this dissertation focusesonfour crucial techniques:radio frequency interference (RFI) suppressiontechniques,SAR ECCM techniques for active blanket jamming, SAR ECCM techniques for activedeceptive jamming, SAR ECCM effectiveness measure.Chapter1illustrates the background and significance of this research subject，andintroduces the present research status of SARtechniques, SAR ECM techniques andSAR ECCM techniques. The major research efforts of this dissertation are alsoexplained．Chapter2studies the radio frequency interference (RFI) suppressiontechniques forSAR.Based on the RFI characteristics of high power and narrow band, some novel RFIsuppressionmethods based on eigen-decomposition is proposed. One of the methods forRFI suppression is based on the dual-north filter in the frequency domain, whichnotches the received signal and the template signal simultaneously, which minimize thecorrelation peak loss to improve the performance. Another method is a novel adaptivefiltering method based on complex empirical mode decomposition (CEMD), whichdecomposes the RFI contaminated signal into a finite and often small number ofIntrinsicMode Function (IMF), and the sum of some selected IMFcomponents is takenas reference input of adaptive filter.Last but not least, a novel singular valuedecomposition method is proposed, which decomposes the singular vectors of thereceived signal with RFI into interference subspace and signal subspace, andtheorthogonality of the two subspaces is used to suppress the RFI.Chapter3studies the SAR ECCM techniques for active blanket jamming. First,thebasic principle of the blanket jamming is introduced, and then the active blanketjamming methods are divided into direct-pathblanket jammingand scatter-wave blanketjamming. For the direct-path blanket jamming, the space/slow-time STAP based methodis studied; and for the scatter-wave blanket jamming, t the method based on the combination of Fast-time STAP and Pulse diversity is studied is studied.Chapter4studies the SAR ECCM techniques for active deceptive jamming.First,the basic principle of the deceptive jamming is introduced, and then the activedeceptive jamming methods are divided into direct-path deceptive jammingandscatter-wave deceptivejamming. For the direct-path deceptive jamming, thespace/slow-time STAP based method is studied; and for the scatter-wave deceptivejamming, the space/fast-time STAP method is studied.Chapter5studies the methods for SAR ECCM effectiveness measure. For theactive blanket jamming, the methods for ECCM effectiveness measure are divided intosubjective evaluation methods and objective evaluation methods. For the subjectiveevaluation, the improvement factor of image quality grade was introduced, and a imagequality grade evaluation criteria based method was proposed; and for the objectiveevaluation, the echoenergy based evaluation method and the image quality index basedevaluation method were proposed, and the specific evaluation indexes were given.Forthe active deceptive jamming, the subjective evaluation methods for ECCMeffectiveness measure are proposed, which is based on the correlation coefficientandEuclidean distance of SAR images.Chapter6summarizes the main work and innovations of the dissertation，and looksforward to thefuture work．更多还原