雷达信号中的微多普勒信息提取方法与应用研究

发布时间：2018-08-17 14:23

【摘要】：雷达目标识别是当今的一个重要的学术方向,在战场监视、防空反导和生命探测等领域发挥着十分重要的作用。实际中目标的运动形式大多是复杂的运动。传统的识别方法无法精确刻画目标的运动状态,已经不能满足应用的需求。近年来,许多学者发现通过对目标微多普勒特征进行分析和研究有助于目标的精确识别。因此,关于微动特征的研究已经吸引了越来越多科研人员的兴趣。对于微多普勒信息的提取方法,近些年已经有了一些研究,但在双站合成孔径雷达的情形下对于微多普勒信息提取方法的研究还较少,并且对于杂波干扰的重视程度也不够。本文首先阐述微动和微多普勒效应的概念,建立雷达目标微多普勒效应的理论模型,通过数学建模得到了振动、旋转等基本的微动所产生的微多普勒频率的理论表达式,找到了微多普勒信息与微动目标运动状态的关系。然后,对时频分析方法进行研究,并对常用的时频分析方法进行性能分析与讨论。本文将在双站合成孔径雷达的情形下,结合相位中心偏置天线(DPCA)技术,提出一种旋转物体微多普勒效应的提取方法,进行建模并给出相应的理论表达式,进行仿真以验证提出的方法的正确性。通过进一步分析得到的仿真结果,反演出描述旋转目标中心位置和运动形式的参数,将此与实际值进行比较,更好的说明提出的方法的正确性。并对所提出的方法进行推广,探索一种利用主旋翼和尾翼运动产生的微多普勒信息进行直升飞机检测的新方法。
[Abstract]:Radar target recognition is an important academic field, which plays an important role in battlefield surveillance, anti-missile defense and life detection. In practice, the moving form of the target is mostly complex motion. The traditional recognition method can not accurately describe the moving state of the target, and can not meet the needs of application. In recent years, many scholars have found that the analysis and study of the micro-Doppler characteristics of the target is helpful to the accurate recognition of the target. Therefore, the research on fretting characteristics has attracted more and more researchers' interest. In recent years, there have been some studies on the extraction of micro-Doppler information, but in the case of bistatic synthetic aperture radar, the research of micro-Doppler information extraction method is less, and the clutter interference is not paid enough attention to. In this paper, the concepts of fretting and micro-Doppler effect are introduced, and the theoretical model of micro-Doppler effect of radar target is established. The theoretical expressions of micro-Doppler frequency caused by vibration, rotation and other basic fretting are obtained by mathematical modeling. The relationship between the micro Doppler information and the moving state of the fretting target is found. Then, the time-frequency analysis method is studied, and the performance of the commonly used time-frequency analysis method is analyzed and discussed. In this paper, in the case of bistatic synthetic Aperture Radar (SAR), a method of extracting micro-Doppler effect of rotating object is presented, which is based on the (DPCA) technique of phase center offset antenna, and the corresponding theoretical expression is given. Simulation is carried out to verify the correctness of the proposed method. Through further analysis of the simulation results, the parameters describing the center position and motion form of the rotating target are presented in reverse, and compared with the actual values, the correctness of the proposed method is better explained. The proposed method is extended to explore a new method for helicopter detection using the micro-Doppler information generated by the motion of the main rotor and the tail wing.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN957.51

【共引文献】