【作者】 张林；

【导师】 朱灿焰；

【作者基本信息】 苏州大学 ， 电子与通信工程， 2011， 硕士

【摘要】 合成孔径雷达(Synthetic Aperture Radar,简称SAR)是一种通过信号分析技术来构建一个等效长天线,以获得高方位分辨率的雷达新技术。它可以全天时、全天候工作,且具有可以穿透一定遮蔽物成像和测绘带距航迹远等优点。被广泛应用于军事领域和地质勘探、地形测绘及海洋应用等多个国民经济领域,发展非常迅速。本文对合成孔径雷达成像原理进行了简要说明,分析了SAR方位向高分辨原理；给出了SAR回波一维、二维信号模型,研究了线性调频信号的性质；对RD算法中匹配滤波器和RCMC的几种实现方式进行了比较,对不同方式下的成像结果进行了评估,发现RCMC采用sinc插值或频域线性相移方法时,成像结果最优；分析计算了聚焦深度,对距离向因离参考点较远引起的散焦问题提出了解决方法；模拟仿真了正侧视条件下的RD算法；分析说明了BP算法成像原理,详细推导了载波恢复、升采样和网格划分等关键问题的处理步骤；模拟仿真了正侧视条件下的BP算法,并对相关结果进行了评估。最后,论文将BP成像算法应用到了一种超宽带穿墙雷达系统中,取得了比较好的算法处理效果。更多还原

【Abstract】 Synthetic aperture radar (SAR) is a new kind of radar techonology, in which a theoretical wider antenna is built through signal analysis techniques to obtain a fine azimuth resolution. It can work all-time and all-weather, and can penetrate some shelters with imaging and map with the advantage of far from the swath, so SAR is widely used in military fields and some areas of national economy as geological exploration, topographical mapping, ocean studings and so on, developing very fast.The paper firstly gives a brief description to the principle of SAR imaging and analyses the principle of fine azimuth resolution. Secondly, provides the simulation of one-dimentional and two-dimentonal signal models and studies the characters of chirp signal. Thirdly, imaging results of different macthed filtering devices and RCMC modes are evaluated and compared, discovering that the result will be optimal if RCMC is achieved with sine interpolation or linear phase shift method in frequency domain. Forthly, caculates and analysis the focusing depth and puts forward some solutoins to deal with the defocusing when the target point is far from the reference point. And then, provides the simulation of RDA in zero squint case. Fifthly, analyses the principle of BPA, and derivates the key issues of carrier recovery, sampling and meshing in details. Following with the simulation of BPA and the evaluations of the results.At end of this paper, the BP imaging algorithm is applied in an ultra wideband through-wall radar system. The imaging results show the BP algorithm is achieved better effects than applied other imaging algorithms, especially in the aspect of imaging on slowly moving object.更多还原