【作者】 刘欣；

【导师】 王任；

【作者基本信息】 电子科技大学 ， 物理学， 2024， 硕士

【摘要】 时间反演电磁波因其空时同步聚焦特性及在恶劣环境中的鲁棒性,在场赋形、成像、逆设计、目标定位、无线电力传输、无线通信等领域被广泛应用。本文聚焦于时间反演技术在电子战领域的应用,为使时间反演技术在实际战略部署中更好地发挥优势,本文从三个子研究方向进行了研究,即用于己方通信的亚波长聚焦传输技术研究、用于对敌干扰的聚焦干扰技术研究以及为保证战场上己方设备的隐蔽性和反侦察能力的反相位干涉仪测向研究。本文的主要研究内容如下:第一部分主要对用于己方通信的时间反演亚波长聚焦传输技术进行了研究。首先指出点汇附近非因果格林函数时间反演场的超分辨率聚焦特性,并从空间聚焦图像和空间谱域的角度分析此特性,还观察到了凋落波与传播波之间自发的时变的转化现象。接着分析了不同吸收率对超分辨率聚焦的影响。基于这些发现,选择单极子天线作为点汇在平行板中进行仿真验证理论分析。最后经仿真和实测,用金属谐振腔中的传统MIMO天线实现了时间反演亚波长聚焦传输。第二部分主要对用于对敌干扰的时间反演聚焦干扰技术进行了研究。首先提出基于信号处理方式的简单理想环境超远距离时间反演仿真方法。然后用提出的方法完成了“30 km地对地”、“100 km地对空”这两种典型聚焦干扰场景的时间反演仿真。接着,讨论了时间反演镜节点机动性的影响以及信噪比对聚焦结果的影响。最后探究了短波电离层信道复杂环境中超远距离时间反演仿真的实现方式。第三部分主要对时间反演来波的反相位干涉仪测向能力进行了研究。首先给出相位干涉仪对时间反演来波和传统干扰来波的理论来波角度估计结果。然后,通过Matlab仿真的方式考察了单基线相位干涉仪、多基线一维线阵干涉仪以及均匀圆阵干涉仪测向系统对传统干扰来波和时间反演来波的测向性能。最后,讨论了干涉仪系统内外部因素带来的相位测量误差对测向结果的影响。本文的研究表明,通过设计基于时间反演的亚波长聚焦传输方法,验证在时间反演通信系统中使用普通MIMO天线的可行性,用于己方军事通信中可不加载额外结构实现间距小于半波长的阵列排布;通过对超远距离时间反演聚焦干扰的仿真实现,为后续进行演示验证、工程实现提供了参考;通过对时间反演干扰来波反相位干涉仪测向能力的研究,发现时间反演来波可对干涉仪产生角度欺骗效果,实战中可防止己方设备被敌方侦察并反击,增强了设备的隐蔽性和生存能力。更多还原

【Abstract】 The time reversal(TR)electromagnetic technique has been widely used in the field shaping,imaging,inverse design,target location,wireless power transfer,wireless communication,and so on,due to the spatial-temporal simultaneous focusing characteristic and robustness in harsh environments of TR waves.In order to make the TR technology play a better role in electronic counter measures,this dissertation focuses on the application of TR technology in the field of strategic communication,and conducts research in three sub-directions,which are the subwavelength focused transmission for self-communication,the focused jamming for electronic counter measures,and the deceptive performance of TR waves for phase interferometer for the purpose of counter-reconnaissance.The main contents in this dissertation are introduced in the following.In the first part,the TR subwavelength focused transmission for selfcommunication is investigated.Firstly,it is proposed that the anti-causal Green’s function based TR field can exhibit super-resolution focusing property,which is analyzed from the perspectives of spatial distribution patterns and spatial spectrums,and the spontaneous time-varying evanescent-to-propagating wave conversions are observed.What’s more,the effect of different absorption rates,on the super-resolution focusing is analyzed.For demonstration,the omnidirectional receiving monopole is regarded as a special kind of wave absorber,and the simulation are conduct with parallel plates.Finally,the subwavelength focused transmission is realized with a conventional decoupled MIMO antenna in a metallic resonant cavity by simulation and measurement.In the second part,the TR focused jamming used for electronic counter measures is studied.Firstly,an ultra-long-distance TR simulation method based on the signal processing suited in the simple ideal environment is proposed.Then,the TR simulation of two typical jamming scenarios,namely,"30 km ground-to-ground" and "100 km ground-to-air" are completed.What’s more,the effects of the maneuverability of the TR mirrors and the signal-to-noise ratio(SNR)on the focusing results are discussed.Finally,the realization of ultra-long-range TR simulation in the short-wave ionospheric channel is explored.In the third part,the deceptive performance of TR waves for the phase interferometer is investigated.Firstly,the nature of direction-finding resistant property of TR incoming waves to phase interferometer is analyzed theoretically,compared with the analysis of conventional incoming waves.Then,one-dimensional DOA estimations in the case of single-baseline linear array,multiple-baseline linear array and uniform circular array phase interferometers are considered for conventional and TR incoming waves respectively to demonstrate the theoretical analyses.Finally,the effects of phase measurement errors brought by internal and external factors of the interferometer systems on the direction-finding results are discussed.The research in the dissertation indicates that,through the design of subwavelength focused transmission method based on TR,the feasibility of utilizing ordinary MIMO antennas into the TR communication system can be verified,which can be used for military communication to increase the communication capacity without loading additional structures.Through the simulation of ultra-long-range TR focused jamming,it can fill up the vacancy of the realization of TR simulations for tens of kilometers under the electronic counter measures’ needs.The discovery of the deceptive performance of TR waves for the phase interferometer can prevent the equipment of our side from being reconnaissance and counterattack by the enemy in the actual combat,and enhance the covertness and survivability of the equipment.更多还原