基于调频连续波信号的圆弧式合成孔径雷达成像方法

摘要

Arc Synthetic Aperture Radar (Arc-SAR) is a new operation-mode radar that is suitable for wide observation in certain areas. With its high resolution, wide observation area, and short repetition visit period, Arc-SAR is widely used in monitoring deformation measurements, landslides, and natural hazards. Because of the special movement of Arc-SAR, the BackproPagation Algorithm (BPA) is widely used in its image processing. Here, we propose a novel two-dimensional frequency domain algorithm to process an Arc-SAR signal. First, we derive a signal model of Arc-SAR based on that of frequency-modulated continuous-wave radar. Next, because the length of the arm is far shorter than the distance of the antenna to the target, the signal can be processed in a 2D frequency domain. Finally, we analyze the error of the frequency method used. This algorithm has the advantages of high computation speed and accuracy. The simulation and experimental data results confirm the effectiveness and validity of the proposed method.%圆弧式合成孔径雷达是一种对特定地区持续监测的新模式雷达，具有分辨率高，观测范围广，重访周期短等特点，适合对特定地区的形变监测以及对塌方、滑坡等灾害的预警。针对圆弧式合成孔径雷达特殊的运动形式，该文提出了一种新的用于调频连续波体制Arc-SAR成像的2维频域算法。首先推导了Arc-SAR的信号模型，然后提出了在满足转动机械臂长远小于目标最短斜距的情况下使用2维频域算法来聚焦信号，之后分析了算法误差。该算法可以在假设条件下对目标准确聚焦，并具有计算速度快等优点。最后使用仿真和实测数据验证了算法的有效性。