【作者】 黄志文；

【导师】 鲁昌华；

【作者基本信息】 合肥工业大学 ， 电路与系统， 2003， 硕士

【摘要】 合成孔径雷达是一种重要的对地观测设备。自1971年R.Keith Rancy首次提出低速运动目标造成图像模糊和动目标检测的原理以来，动目标检测即成为合成孔径雷达领域中研究的热点之一。由于动目标运动的不可知性以及合成孔径雷达安装平台的运动造成杂波频谱的扩展等因素的影响，使动目标的检测变得异常困难。本文的研究内容是在真实机载SAR回波数据基础上，寻找一种适合处理这种数据的技术，来检测动目标。本文所做主要工作如下： 1．本文对合成孔径雷达的工作原理、目标运动对成像的影响、动目标信号的回波建模及单通道下动目标检测的性能做了较系统的研究和总结，并就两种较实用的动目标检测方法(反射特性位移法和前置滤波法)进行了研究和比较。 2．对机载SAR杂波锁定、自聚焦算法进行了研究和探索，并用它们处理真实回波数据，为进一步在强杂波环境下检测动目标研究提供了参考。 3．重点研究了将线性调频信号加随机噪声的模型引入动目标检测。根据雷达系统的主要工作参数，在近似的基础上，仿真了动目标数据。用仿真的数据作源数据，用WVD和Hough变换结合的方法来估计两个重要参数(多普勒中心频率和多普勒调频率)，实验表明在较高信噪比下可以取得较好效果。更多还原

【Abstract】 Synthetic Aperture Radar is one of the important devices for surveying the ground. Since Mr. R.Keith Rany first proposed that the low moving targets cause the illegibility on the synthetic aperture radar (SAR) image and the theory of the moving targets detection in 1971, the moving targets detection has been one of major hot topics in the field of SAR technology. However, the detection on the moving targets becomes very difficult because of the clutter spectrum spreading due to the unknown targets moving and the radar’s carrier moving. In this paper, we intended to find out a suitable technology based on the real SAR echo data to process that data. The main results we have gained in this topic included three aspects as following:1. We have studied the systemic theories about this research project such as SAR imaging, the factors that affected the SAR imaging for the moving targets, modeling for the moving targets signal and the detection ability under single channel SAR system. More over I have studied and compared the practical (reflectivity displacement method) RDM and the digital pre-filter methods in SAR moving targets detection.2. We processed the real data with Clutter Locking and Auto Focus algorithms and gained the experience for the further research. That gave a reference to the advance research of the moving targets detection on the condition of the heavy cluster.3. We used chirp signal plus radon noise as signal model and have simulated the echo data by compute under the ideal conditions according to the real parameters of the SAR system. Two important parameters (Doppler center and Doppler shift) are estimated by the method of combining the Winger-Ville-Distribute (WVD) and Hough in the case of using the simulating data as source data, and it could get the effective results on high Signal-Noise Ratio (SNR) in the experiments.更多还原