雷达目标微动参数估计技术研究

发布时间：2018-01-12 06:35

本文关键词：雷达目标微动参数估计技术研究　出处：《国防科学技术大学》2014年硕士论文　论文类型：学位论文

【摘要】：目标微动特征包含目标特有的结构信息、运动信息,可用作目标识别的重要依据,对目标微动特征的研究已成为雷达目标探测与识别领域的一个新的技术热点。本文重点研究平动条件下微动目标对雷达回波的调制效应及目标微动参数估计问题。针对目标平动与微动的耦合特点,提出三种微动参数估计方法,实现了平动条件下目标的微动参数估计。第一章介绍课题的研究背景及意义,概括目标微动的研究现状,从微动目标雷达回波调制模型、雷达回波分量分离、微动特征提取、平动补偿四个方面总结该领域的主要技术途径。最后介绍本文研究工作和结构安排。第二章重点分析平动条件下雷达微动目标对回波的调制效应。首先结合空间进动目标的运动模型、散射中心模型和目标散射强度的变化规律建立了目标的宽窄带雷达回波调制模型,在此基础上深入分析平动条件下微动目标雷达回波的功率调制特性、微多普勒调制特性、微距离调制特性、平动的多普勒调制特性以及目标平动与微动的耦合作用。第三章研究平动条件下基于雷达窄带、宽带信号的目标微动参数估计方法。对于窄带信号,首先推导了微多普勒信号的时频分布的周期性,证明在平动条件下回波时频分布的周期性将演变为循环周期性,在此基础上引进循环相关系数以刻画时频分布的循环周期性,进而估计出微动周期。对于宽带信号,首先研究了目标散射中心瞬时距离的提取方法,在此基础上,提出基于高阶差值序列的微动周期估计方法。基于循环相关系数和基于高阶差值序列的微动周期估计方法实现了平动条件下目标的微动参数估计。第四章研究复杂平动条件下的微动参数估计方法。针对目标机动等复杂平动,受数学中微元法的启发,提出基于分段平动补偿的回波平动补偿方法,最大限度地补偿了目标平动。同时引进一种基于扩展数据的时频计算方法,极大地抑制了时频分布的边缘效应,提高了瞬时频率的估计精度。受具有平移不变性的差值算子的启发,提出基于时频差值平方和序列的微动频率估计方法。时频差值平方和序列能够消除目标残余平动的影响,同时避免了雷达回波分量的分离。分段平动补偿和时频差值平方和序列的结合实现了复杂平动条件下的目标微动参数估计。第五章总结了论文的主要工作和创新点,指出需要进一步研究的问题。
[Abstract]:Target micro motion feature contains structural information specific to target motion information, can be used as an important basis for the research of target recognition, target micro motion feature has become a new hotspot in the field of technology of radar target detection and recognition. Estimation of modulation effect on the radar echo of micro motion targets this paper focuses on the translational conditions and target motion parameter. According to the coupling characteristics of the target translation and motion estimation method is proposed, three kinds of micro parameters, the motion parameter estimation of target translational conditions. The first chapter introduces the research background and the significance of the topic, research status quo summary of micro motion target, from the micro target radar echo modulation model, separation of radar echo components, micro motion feature extraction, four summarize the main aspects of translational motion compensation technology in the field. Finally this research work arrangement and structure. The second chapter focuses on the analysis of translation conditions The modulation effect of the backscattered wave under the radar target. Firstly the motion model of micro space precession target, variation of scattering center model and target scattering intensity of targets is established the narrowband radar echo modulation model, on the basis of in-depth analysis of translation under the condition of target micro power modulation characteristics of the radar echoes, the modulation characteristics of micro micro Doppler. The distance modulation characteristic, translational Doppler modulation and the goal of translation and fretting coupling. Based on narrowband radar under the third chapter studies the translation conditions, estimate the target motion parameter of wideband signal. For narrowband signals, the frequency distribution of the first periodic micro Doppler signal is proved under the condition of echo in translational periodicity frequency distribution will evolve into the cycle, on the basis of the introduction of circular correlation coefficient in cycle frequency distribution characterization, and The estimated motion period. For broadband signals, firstly study the extraction method of target scattering center instantaneous distance, based on the proposed estimation method of fretting cycle based on high order difference sequence. Based on cyclic correlation coefficient and the method based on motion parameter estimation of target under the condition of translational motion period of high order difference sequences of estimation. Under the condition of complicated translational motion parameter estimation method. The fourth chapter according to the target maneuver complex translation, inspired by the infinitesimal method in mathematics, the echo of translational motion compensation method based on piecewise motion compensation, the maximum compensation target. Translation and introduction of a new calculation method of time-frequency expansion based on the data, greatly reduced the edge effect of time-frequency distribution, improve the estimation precision of instantaneous frequency. Inspired by the difference operator with translational invariance, is proposed based on the time-frequency plane difference Fretting frequency estimation method and sequence. When the frequency difference between square and sequence can eliminate the influence of target motion while avoiding the residual, separation of radar echo components. Combined with a piecewise translational motion compensation and time frequency difference square and sequence to achieve the target motion parameter estimation under complex conditions of translation. The fifth chapter summarizes the main work in this paper and innovation, points out the problems that need further study.

【学位授予单位】：国防科学技术大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN957.51

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