雷达目标微多普勒特征分析及其应用

发布时间：2018-06-01 00:19

本文选题：雷达目标识别 + 微运动　；参考：《西安电子科技大学》2014年博士论文

【摘要】：随着目标识别技术的快速发展,各种反探测、反识别的技术也获得了快速发展,为目标的探测与识别带来了新的困难,同时也对目标探测与识别提出了更高的技术要求,越来越要求对目标细节的描述及运动状态的精细刻画。雷达目标微运动产生的微多普勒特征包含着目标的运动和结构信息,从中可提取出微动目标固有的特性。自从雷达目标微多普勒特征被发现以来,其在目标探测、分类与识别领域的重要价值已经引起了国内外学术界和工程界的广泛关注。因此,深入研究雷达目标的微多普勒特征及其在军事和民用领域的应用具有重要的理论及应用价值。本文主要围绕雷达目标的微运动产生的微多普勒特征数学分析、微多普勒特征提取方法、微动信号分离及微多普勒特征在微动参数估计和目标识别中的应用等方面展开研究,论文主要工作有以下几个方面:1.研究了微多普勒特征的产生原理,建立了加速、振动、旋转、锥旋、摆动等典型微动模型,推导了其产生的微多普勒特征的数学表达式及其与微运动参数之间的对应关系;针对目标微运动特征的复杂性和差异性,以有旋翼和无旋翼目标识别为研究背景,建立了具有平动、加速与振动运动特征的复合运动微动模型和具有平动、加速、振动及旋转运动特征的复合运动微动模型,推导了两种复合运动产生的微多普勒特征及其与目标结构和微运动参数的关系,比较了其微多普勒特征的差异性,为识别这两类目标奠定了理论基础。2.针对微多普勒特征的提取问题,研究了从微动目标雷达回波中提取微多普勒特征的常用方法,并分析了各自的优缺点,提出了使用重排平滑伪Wigner-Ville分布提取目标微多普勒特征的方法,该方法能够有效地提取微动信号的微多普勒特征;研究了运动目标的平动速度、加速度、雷达的载频和雷达PRF对提取微多普勒特征的影响及相应对策,为有效提取雷达目标微多普勒特征提供了理论指导。3.提出了基于Radon变换的目标主体信号与微动信号的分离方法,首先对回波信号进行时频变换,然后在时频平面上通过Radon变换来分离目标主体信号与微动信号,再通过逆Radon变换得到分离信号的时频分布;针对常见微动信号表现为正弦调频信号的特点,提出了基于时频分析和相关搜索法的正弦调频信号的分离方法,首先在时频域采用时频分析的方法预估计信号的类别和相关参数范围,进而在时域通过相关法搜索参数对多分量正弦调频信号进行分离。4.提出了利用提取时频分析矩阵频率向最大值的峰值提取和最小二乘拟合直线相结合估计目标微动参数的方法,通过该方法有效地估计了加速与振动目标的加速度、振动频率和振动幅度;估计了加速与旋转目标的加速度、旋转角速度及旋转半径;在此基础上,建立了线性旋转刚体目标的微动模型并分析了其产生的微多普勒特征,估计了线性旋转刚体目标的旋转角速度及刚体长度;进而,建立了直升机旋翼目标的微动模型,分析了其产生的微多普勒特征,估计了直升机旋翼旋转角速度、旋翼长度和旋翼叶片数,为对目标进行精确识别奠定了基础。5.针对真假弹头的辨识问题,建立了锥体弹头进动、章动和诱饵目标摆动的微动模型,分析了它们产生的微多普勒特征,比较了弹头的进动、章动和诱饵摆动所具有的不同的微多普勒特征,提出了依据微多普勒特征的差异性对真假弹头进行辨识的方法;针对轮式车和履车带车辆的辨识问题,建立了轮式车和履带车的微动模型,分析了轮式车和履车带车辆产生的微多普勒特征及其差异性,提出了依据微多普勒特征的差异性对轮式车和履车带车辆进行辨识的方法。
[Abstract]:With the rapid development of target recognition technology, various anti detection and anti recognition technologies have also gained rapid development. It brings new difficulties for target detection and recognition. At the same time, it also puts forward higher technical requirements for target detection and recognition, and more and more demands for the description of target details and fine depiction of motion state. The micro Doppler features produced by the motion include the motion and structural information of the target, which can extract the inherent characteristics of the micro moving target. Since the detection of the radar target micro Doppler features, the important value in the field of target detection, classification and recognition has aroused wide attention from both the academic and Engineering circles at home and abroad. The micro Doppler characteristics and its application in military and civil fields are of important theoretical and practical value. This paper mainly focuses on the mathematical analysis of the micro Doppler characteristics produced by the micro motion of radar targets, the extraction method of micro Doppler features, the separation of micro signal and the micro Doppler feature in the estimation and the mesh of the micromotion parameters. The main work of this paper is as follows. The main work of this paper is as follows: 1. the principle of micro Doppler characteristics is studied, and the typical microdynamic models of acceleration, vibration, rotation, cone rotation and swing are established, and the mathematical expressions of the micro Doppler characteristics and the correspondence between the micro motion parameters and the corresponding relations are derived. With the complexity and difference of the feature of the target micro motion, the compound motion micromotion model with the characteristics of translational, acceleration and vibration motion is established, and the compound motion model with the characteristics of translational, acceleration, vibration and rotation motion is established. The microdynamics of two kinds of compound motion are derived. The characteristic of.2. and its relation to the target structure and the micro motion parameters, and compare the difference of their micro Doppler characteristics. In order to identify these two kinds of targets, it lays a theoretical foundation for the extraction of micro Doppler features, and studies the common methods of extracting the characteristics of micro Doppler from the echo of the moving target radar, and analyzes their respective advantages and disadvantages. The method of extracting the target micro Doppler features using the rearrangement smooth pseudo Wigner-Ville distribution is proposed. This method can effectively extract the micro Doppler characteristics of the moving signal, and study the influence of the moving speed of the moving target, the acceleration, the carrier frequency of the radar and the radar PRF on the extraction of the micro Doppler characteristics and the corresponding countermeasures. The radar target micro Doppler features provide theoretical guidance for.3.. The separation method based on Radon transform is proposed for the target main signal and the microdynamic signal. First, the time frequency conversion is carried out on the echo signal, then the target body signal and the fretting signal are separated by the Radon transform on the time frequency plane, and then the separated signal is obtained by inverse Radon transform. In view of the characteristics of the common fretting signal as sine frequency modulation signal, the separation method of sinusoidal frequency modulation signal based on time frequency analysis and correlation search method is proposed. First, the classification of the signal and the range of related parameters are preestimated by time-frequency analysis in time and frequency domain, and then the correlation method is used to search for more parameters in time domain. The component sinusoidal frequency modulation signal is separated by.4.. A method is proposed to estimate the microdynamic parameters of the target by extracting the peak value of the time frequency analysis matrix and the least square fitting line. The acceleration, the vibration frequency and the amplitude of the vibration are estimated effectively by this method, and the acceleration and rotation are estimated. The acceleration of the target, the rotational angular velocity and the rotation radius, and on this basis, the microdynamic model of the linear rotating rigid object is established and the micro Doppler characteristics are analyzed. The rotation angular velocity and the rigid body length of the linear rotating rigid object are estimated, and then the microdynamic model of the helicopter rotor target is established, and its production is analyzed. With the characteristics of micro Doppler, the rotational angular velocity of the helicopter rotor, the length of the rotor and the number of rotor blades are estimated. For the accurate recognition of the target, the identification of the true and false warhead is established by the accurate recognition of the target. The microdynamic model of the cone warhead precession, the nutation and the swinging of the decoy target is established, and the micro Doppler characteristics of the.5. are analyzed, and the comparison is made. The different micro Doppler characteristics of the precession of the warhead, the nutation and the bait swing, and the method of identifying the true and false warheads according to the difference of the characteristics of the micro Doppler. The fretting model of the wheeled vehicle and the caterpillar car is established for the identification of the wheeled vehicle and the track car, and the vehicle and the car belt vehicle are analyzed. Based on the characteristics of micro Doppler and their differences, a method of identifying wheeled vehicles and carriages with vehicles based on the difference of micro Doppler features is proposed.
【学位授予单位】：西安电子科技大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TN957.51

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