合成孔径雷达（Synthetic Aperture Radar，SAR）成像是一种先进的遥感技术，在诸多军用、民用领域有着广泛的应用。现代SAR成像应用对高分辨率和宽测绘带的要求不断提高，而单通道SAR系统中方位向分辨率和距离向测绘带宽之间存在固有的矛盾。本文围绕高分辨率宽测绘带SAR成像这一应用需求，基于稀疏优化理论方法开展了针对单通道SAR的高分宽幅成像体制的研究，从信号采样模式、稀疏优化模型以及成像算法等关键环节入手，主要完成了以下两部分工作：1）针对单通道SAR系统中方位向分辨率和距离向测绘带宽之间存在“最小天线面积”的固有约束的问题，提出了适用于高分宽幅SAR成像体制的方位向脉冲发射模式。本文首先从高分辨率和宽测绘带之间的矛盾入手，引入在方位向通过随机采样模式抑制欠采样条件下的混叠现象，然后对不同采样模式的抗混叠性进行了分析，最终基于Poisson disk采样设计了方位向脉冲发射模式。Poisson disk采样保证了相邻两个发射脉冲之间的采样间隔大于某个最小时间间隔，同时可以在欠采样的条件下很好地抑制混叠现象。相比于传统的均匀脉冲发射模式，Poisson disk采样模式提供了获取更大的距离向测绘带宽的潜力。2）基于稀疏优化理论，本文提出了适用于方位向Poisson disk脉冲发射模式的高分宽幅SAR成像算法。本文从传统的Chirp Scaling算法入手，基于近似观测模型构建回波模拟算子，从而建立基于Poisson disk采样的SAR成像稀疏优化模型，然后运用软阈值迭代算法对优化模型进行求解，实现了单通道SAR系统的高分辨率宽测绘带成像。本文在仿真实验和RADARSAT-1与“高分三号”的实测SAR数据上验证了成像算法的有效性。

Synthetic aperture radar (SAR) is an advanced remote sensing technology, which is widely used in a number of military and civilian applications. In modern SAR imaging applications, the demands of high spatial resolution and wide imaging swath are constantly increased. However, there exists a tradeoff between the azimuth resolution and the range swath width in single channel SAR systems. In this thesis, we focus on the requirements of high-resolution wide-swath (HRWS) SAR imaging, and study the HRWS imaging systems of single channel SAR based on theories and methods of sparse optimization. We start with several key aspects including signal sampling pattern, the sparse optimization model and the imaging algorithms, and mainly complete the following two parts of work.1) To deal with the inherent “minimum SAR antenna area constraint” between azimuth resolution and range swath width in single channel SAR systems, a pulse repetition pattern in the azimuth direction which is adapted to the HRWS imaging systems is proposed. In this thesis, we start with the contradiction between high resolution and wide swath, and introduce the stochastic sampling to suppress the aliasing phenomena caused by under-sampling. Then we analyze the antialiasing capabilities of different stochastic sampling patterns and finally formulate the azimuth pulse repetition pattern via Poisson disk sampling. Poisson disk sampling can not only ensure that the interval between any two adjacent pulses is longer than a desired minimal interval, but also suppress the aliasing phenomena under sub-Nyquist sampling conditions. Compared with the traditional uniform sampling pattern, Poisson disk sampling pattern provides the potential to widen the swath width in the range direction.2) Based on the Poisson disk sampling pattern in the azimuth direction, a sparsity-driven HRWS SAR imaging method is proposed in this thesis. Firstly, we introduce the traditional chirp scaling algorithm and form the sparsity-driven SAR imaging model adapted to Poisson disk sampling by constructing the echo simulation operator based on the approximated observation. Then the iterative shrinkage/thresholding algorithm is adopted to realize the HRWS imaging in single channel SAR systems. The experimental results on simulations and the real SAR data on RADARSAT-1 and GAOFEN-3 verify the effectiveness of the proposed method.