机载前视SAR三维成像算法研究

该文以一种采用天线阵模式的机载前视合成孔径雷达(SAR)系统为对象，根据前视SAR的成像几何模型和回波信号特点，提出了一种适用于机载前视SAR的3维成像算法。该算法首先将各天线阵元接收一遍后的数据采用CS算法获得单幅SAR图像，然后将飞机飞行过程中获得的所有SAR图像中相同方位向对应的数据结合距离多普勒算法思想依次进行成像处理，最后获得3维像。模拟了X波段前视SAR点目标回波并进行了3维成像实验，对成像性能进行了分析。仿真结果验证了该算法的有效性。

Study on Three-Dimensional Imaging Algorithm for Airborne Forward-Looking SAR

In this paper, an innovative airborne forward-looking SAR system using antenna array is studied, and a new three-dimensional imaging algorithm is proposed for airborne forward-looking SAR based on the image geometry and the characteristic of echo signal. A single SAR image was obtained with chirp scaling algorithm until all the receiving antennas have received echoes once. When plane flies along the track continuously, a sequence of two-dimensional SAR images in front of the flight path can be obtained. Then the three-dimensional image of forward-looking SAR can be obtained by focusing one section at an azimuth position one time with Range-Doppler algorithm until all the sections have been processed. Raw data of forward-looking SAR in X-band is simulated and three-dimensional image is achieved. The imaging result is analyzed, and simulation results confirm the validity of the proposed algorithm.