线性频率分集阵列SAR增强后向投影算法

Linear frequency diversity array synthetic aperture radar imaging based on enhanced back-projection algorithm

在建立线性频率分集阵列合成孔径雷达多载频信号模型的基础上,提出了一种增强后向投影算法.通过对各阵元回波信号进行二次相位误差补偿,并在后向投影过程中增加对目标空变距离偏移量的校正及空变偏移相位的补偿,克服了经典后向投影算法用于频率分集阵列合成孔径雷达成像时存在的图像散焦及几何畸变问题,可实现任意成像几何构型下的目标高精度成像,有效区分相邻强、弱目标.仿真结果验证了该算法的有效性.

Based on the signal model of multiple carrier frequency （MCF） for linear frequency diversity array synthetic aperture radar （LFDA-SAR）, we propose an enhanced back-projection （EBP） algorithm. Compensation for the quadratic phase error in echoes is executed and the spatial-variant range drifting amount and phase of the target are amended during the process of back-projection. The proposed algorithm can effectively rectify the image blurring and geometric distortion problem in classical back-projection imaging results, realize a high precision imaging of targets with an arbitrary imaging geometry and distinguish adjacent strong and weak targets. All results verify the effectiveness of the proposed algorithm.