合成孔径雷达(Synthetic Aperture Radar，SAR)不仅可以实现待测静止场景的高分辨成像，还可以实现待测区域内感兴趣的地面运动目标指示(Ground Moving Target Indication，GMTI)。随着应用要求的不断提高、系统结构的不断优化及处理方法的不断进步，常规低速匀速直线飞行SAR已然不能满足当前需求，这就决定了载荷平台更加多样，运动轨迹趋向复杂的SAR系统及相应信号处理算法需要进一步被发掘。其中，雷达载荷平台在飞行过程中伴随单／三维加速度甚至高阶加速度矢量的高速机动飞行SAR近期受到了广泛关注。由于具有迫切、实用的军事民用需求，自主、安全的探测成像环境和灵活、及时的响应重访能力，高速机动飞行SAR往往更适应于雷达及其载荷平台的实际工作环境。但对于高速机动飞行SAR-GMTI技术而言，一方面静止场景成像与运动目标指示在体制上的明显差异制约了现有SAR静止场景成像方法的直接拓展，而另一方面回波信号特性与内部机理机构在原理上的显著不同制约了常规SAR运动目标指示方法的直接应用。为此，本文以回波模型的建立为基础，从运动目标提取和运动目标处理两个方面开展高速机动飞行SAR-GMTI的研究，主要包含以下四个内容： 一、建立了高速机动飞行单／多通道SAR静止／运动目标的回波信号矢量化统一模型。考虑到雷达载荷平台高速机动飞行所引入的三维加速度会改变其飞行姿态，进而导致常规恒定瞬时基线模型产生显著的相位误差，本部分以运动学原理为基础，从矢量分析的角度综合考虑静止／运动目标的特点和雷达天线通道的刚体特性，并巧妙融入了雷达载荷平台高速机动飞行对各通道之间瞬时基线变化的影响。仿真实验表明，本文所提的统一模型可以有效避免常规恒定瞬时基线模型在高速机动飞行SAR信号处理中引入的相位误差。 二、提出了一种多通道非自适应运动目标提取方法。考虑到经过距离维脉冲压缩处理后的低轨星载多通道SAR回波信号主要包含高阶耦合项、多普勒扩散项和传统空时项，本部分所提方法首先通过非空变相位补偿来消除信号高阶耦合项的影响；随后通过多普勒扩散压缩来消除信号多普勒扩散项的影响；最后通过设计杂波对消器来处理信号的传统空时项，进而完成杂波抑制与运动目标的提取。理论分析表明，相比于传统SAR自适应类运动目标提取方法，本部分所提多通道非自适应运动目标提取方法有效避免了其大量独立同分布训练样本数目要求、运动目标信息先验未知及巨大的计算复杂度等问题；同时，仿真实验表明，相比于非自适应的偏置相位中心天线方法，本部分所提多通道非自适应运动目标提取方法对于雷达系统参数设计的限制较少，且能够容忍较小程度的雷达系统参数测量误差。 三、提出了一种单通道复图像域运动目标提取方法。考虑到经过成像处理之后的高速机动飞行单通道SAR背景杂波具有多普勒谱对称的特性，本部分所提方法首先通过后向投影算法避免常规距离多普勒算法成像失效的问题，随后通过对称多普勒像素处理实现复图像域上的运动目标提取。理论分析表明，相比于传统数据域运动目标提取方法，本部分所提单通道复图像域运动目标提取方法有效避免了其原始数据复原、无杂波假设失效及重复冗余操作等问题；同时，仿真实验表明，相比于同类SAR图像域的对称多普勒视图对消方法，本部分所提单通道复图像域运动目标提取方法不仅可以避免运动目标对消的现象，还可以实现对称多普勒视图存在像素失配时的运动目标提取。 四、提出了一种单通道高效运动目标处理方法。考虑到经过距离维脉冲压缩处理之后的临近空间高超声速飞行器载斜视单通道SAR回波信号存在严重的多普勒模糊并存、距离徙动和方位徙动等问题，本部分所提方法首先通过信号预处理来消除信号多普勒谱模糊的影响，并大幅降低信号多普勒中心模糊；随后通过模糊匹配的楔石形变换来消除信号距离徙动的影响；最后通过高效调频傅里叶变换来消除信号的方位徙动影响。理论分析表明，本部分所提单通道高效运动目标处理方法不仅适用于理想匀速直线飞行的临近空间高超声速飞行器载斜视单通道SAR的单／多运动目标处理，也适用于实际机动曲线飞行的临近空间高超声速飞行器载斜视单通道SAR的单／多运动目标处理；同时，仿真实验表明，相比于同类运动目标处理方法，本部分所提单通道高效运动目标提取方法在保证运动目标处理性能的基础之上，具有较低的运算复杂度。 总体来说，本文对高速机动飞行SAR-GMTI进行了初步的研究，从理论上提出了一些解决方法或思路，以求发掘SAR在军民应用中新的技术途径，并促进SAR理论的发展和方法的实用化。 关键词：合成孔径雷达，运动目标指示，高速机动飞行器，矢量模型，非自适应处理，复图像域处理，高效处理

 Synthetic aperture radar (SAR) can achieve not only high-resolution imaging of the measured stationary scenes, but also achieve ground moving target indication (GMTI) of the interested moving targets in the detected area. With the improvement of application requirements, the optimization of system structures and the improvement of processing methods, the traditional low-speed uniform linear flight SAR can no longer meet the current demand. The problem determines that the platform of future SAR system is more diverse, the trajectory of future SAR platform is more complex, and the corresponding SAR signal processing method should be further explored. Among them, the high speed and maneuvering SAR with single- or three-dimensional acceleration (and even high-order acceleration vector) during the flight has recently received extensive attention. Due to the urgent and practical military civilian demand, independent and safe detecting environment, and flexible and timely revisiting capability, high speed and maneuvering SAR is more suitable for the practical environment of SAR. However, the differences between SAR imaging and GMTI in system restrict the direct expansion of existing SAR imaging methods. Besides, the direct application of traditional SAR-GMTI methods are restricted by the difference of echo signal characteristics and internal mechanism. Based on the establishment of echo signal model, this dissertation studies SAR-GMTI methods for high speed and maneuvering SAR from two aspects: moving target extraction and moving target processing. The main contribution of this dissertation including the following four parts: First, a vectorization signal model of the stationary/moving target for single-/multi-channel high speed and maneuvering SAR-GMTI is established. The three-dimensional acceleration introduced by the high speed and maneuvering flight of the radar platform will change its flight attitude, which will induce severe phase error for conventional instantaneous baseline model. Based on the kinematics principle, the proposed model takes into account the characteristics of the stationary/moving target and the rigid body characteristics of the radar antenna from the perspective of vector analysis, and subtly integrates the effects of high speed and maneuvering of the radar platform on the instantaneous baseline vector variation of multi-channel SAR. Simulation experiments show that the proposed model can effectively avoid the phase error introduced by the conventional constant instantaneous baseline model in high speed and maneuvering SAR signal processing. Second, a multi-channel non-adaptive moving target extraction method is proposed. Considering that the range compressed echo signal of low-orbit space-borne multi-channel SAR contains high-order coupling part, Doppler extension part, and traditional space-time part, the proposed method firstly eliminates the influence of high-order coupling part through non-space-variant phase compensation. Then, the influence of Doppler extension part is eliminated by Doppler extension compression. Finally, the clutter canceller is designed to process the traditional space-time part, so as to suppress the clutter and extract the moving target. Theoretical analysis shows that compared with the traditional SAR adaptive moving target extraction method, the proposed method effectively avoids the requirement of a large number of independent and identically distributed training samples, the prior information of the moving target information and the huge calculation. Meanwhile, the simulation experiments show that compared with the non-adaptive displaced phase center antenna method, the proposed method has fewer restrictions on radar system parameter design and can tolerate a small degree of radar system parameter measurement error. Third, a single-channel complex image domain moving target extraction method is proposed. Considering that the imaged background clutter of high speed and maneuvering single-channel SAR has the characteristics of symmetrical Doppler spectrum, the proposed method firstly complete SAR imaging through the back-projection algorithm to avoid the failure of conventional range Doppler algorithm. Then, the moving target extraction in the complex SAR image domain can be completed by the proposed symmetry Doppler pixel processing. Theoretical analysis shows that compared with the traditional raw-data domain moving target extraction method, the proposed method effectively avoids the problems of raw-data re-transform, failure of clutter-free assumption, and repetitive and redundancy processing. Meanwhile, the simulation experiments show that compared with the symmetric Doppler view cancellation method, the proposed method can avoid not only the phenomenon of moving target cancellation, but also realize the moving target extraction when there exist pixels' mismatch in the two symmetric Doppler views. Fourth, a single-channel efficient moving target processing method is proposed. Considering that the range compressed echo signal of near-space hypersonic vehicle-borne squint-looking single-channel SAR has severe Doppler center and spectrum ambiguity, range migration and azimuth migration, the method proposed in this dissertation firstly eliminates the influence of Doppler spectrum ambiguity and reduce the influence of Doppler center ambiguity through signal pre-processing. Then, the influence of range migration is eliminated by blur matching keystone transform. Finally, the hign-etticiency chirp Fourier transform is processed for the azimuth migration. Theoretical analysis shows that the proposed method is not only suitable for the single/multi-moving target processing of the squint-looking single-channel SAR of the near-space hypersonic aircraft with ideal uniform linear flight, but also suitable for that of the near-space hypersonic aircraft of the actual maneuvering curve flight. Meanwhile, the simulation experiments show that the proposed method has a lower computational complexity compare to the similar methods under the case of achieving same moving target processing performance. In summary, this dissertation conducts a preliminary study on the high speed and maneuvering SAR-GMTI, and proposes some solutions or ideas in theory to explore new technical approaches for SAR in military and civilian applications, and promote the development of SAR theory, and the practical use of methods. Keywords: Synthetic Aperture Radar, Ground Moving Target Indication, High Speed and Maneuvering Aircraft, Vectorization Model, Non-adaptive Processing, Complex Image Domain Processing, High Efficiency Processing