机载SAR动目标检测及参数估计技术研究

发布时间：2018-06-17 23:31

  本文选题：SAR动目标检测 + DPCA　； 参考：《电子科技大学》2014年硕士论文

【摘要】：SAR动目标检测(SAR-GMTI)技术在保证高分辨率的条件下可以实现动目标的检测、测速和定位,在军用和民用领域都具有重要意义,机载SAR具有很大的灵活性,目前世界各国都在努力寻求先进的动目标检测方法,积极研制高性能的机载SAR动目标检测系统。本文主要研究了SAR动目标检测技术以及动目标的测速与定位,主要工作包括:1.通过建立SAR动目标的几何模型,分析了SAR动目标回波的模型,分别从目标运动对多普勒调频斜率和多普勒中心的影响分析了动目标对SAR成像的影响,并且通过RD算法进行了仿真验证;分析了动目标对距离徙动的影响。2.研究了SAR的地杂波和恒虚警处理,深入分析了K杂波模型,对其进行成像。建立了双通道SAR系统慢速运动目标的检测模型,分析了DPCA算法与AT I技术检测动目标基本原理,详细推倒了两者的基本公式,给出检测流程图,并且进行实验仿真验证;分析了DPCA和ATI算法的性能,研究了存在通道误差时对检测性能的影响;在不同信噪比、不同速度和不同信杂比三种情况下对比了两种算法的检测性能,得出了DPCA受噪声影响明显、ATI受杂波影响明显的结论并给出了理论分析。3.分析了分数阶傅里叶变化(FrFT)检测线性调频信号与参数估计原理;利用分数阶傅里叶变换对线性调频信号的筛选性和DPCA对杂波良好的拟制,将DPC A技术与Fr FT有机的结合进行动目标检测与参数估计;建立了三通道DPCA检测动目标的几何模型,采用CFAR技术检测出有动目标后,利用FrFT和双路DPCA信号峰值幅度比进行参数估计,对目标进行测速与定位;研究了多个动目标的检测方法;在含有噪声和杂波的情况下验证了算法的有效性。
[Abstract]:SAR-GMTI (SAR moving Target Detection) technology can realize moving target detection, velocity measurement and positioning under the condition of high resolution. It is of great significance in both military and civil fields, and airborne SAR has great flexibility. At present, countries all over the world are trying to find advanced moving target detection methods, and actively develop high performance airborne SAR moving target detection system. This paper mainly studies the SAR moving target detection technology and the velocity and location of moving target, the main work includes: 1. By establishing the geometric model of moving SAR target, the model of SAR moving target echo is analyzed, and the influence of moving target on SAR imaging is analyzed from the effects of target motion on Doppler frequency modulation slope and Doppler center, respectively. The simulation results are verified by Rd algorithm, and the effect of moving target on range migration is analyzed. The ground clutter and CFAR processing of SAR are studied, and the K-clutter model is deeply analyzed and imaged. The detection model of slow-moving target in two-channel SAR system is established. The basic principle of DPCA algorithm and ATI technique is analyzed, the basic formulas of the two methods are pushed down in detail, the flow chart of detection is given, and the experimental results are verified by simulation. The performance of DPCA and ATI algorithm is analyzed, and the influence of channel error on detection performance is studied, and the detection performance of the two algorithms is compared under three conditions: different signal-to-noise ratio, different speed and different signal-to-clutter ratio. The conclusion that DPCA is obviously affected by noise and ATI is influenced by clutter is obtained and the theoretical analysis is given. The principle of linear frequency modulation (LFM) signal detection and parameter estimation by fractional-order Fourier transform (FrFT) is analyzed, the screening of LFM signal by fractional Fourier transform (FFT) and the good simulation of clutter by DPCA are analyzed. The moving target detection and parameter estimation are carried out by combining DPC A technology with Fr FT, and the geometric model of moving target detection by three-channel DPCA is established, and the moving target is detected by CFAR technique. The parameters are estimated by using FrFT and dual DPCA signal peak amplitude ratio to detect the velocity and location of the target, and the detection method of multiple moving targets is studied, and the effectiveness of the algorithm is verified under the condition of noise and clutter.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN957.52
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本文编号：2032939