叶簇穿透合成孔径雷达增强成像方法

摘要

叶簇穿透合成孔径雷达(FOPEN SAR)为了探测树林中隐藏目标，通常工作在低信杂比(SCR)的环境中，目标检测难度极大。该文提出一种基于目标散射方位变化特性的增强成像方法，在保证高空间分辨率的同时，增强隐蔽目标图像SCR。对于感兴趣的车辆类目标，目标主侧面与地面形成二面角。当电磁波沿二面角法线方向入射时，回波能量最强。该方法能够获得该方位角对应的高分辨率图像，从而增强目标SCR，提高检测性能。实测机载FOPEN SAR数据验证了该方法的有效性。%FOliage PENetration Synthetic Aperture Radar (FOPEN SAR) is used in low Signal-to-Clutter Ratio (SCR) conditions to detect targets hidden in forests, which introduces difficulties in target detection. In this study, an enhanced imaging method based on the scattering aspect variability of the target is proposed, which improves the SCR of the formed images of hidden targets while maintaining high spatial resolution. In the case of a vehicle target, the dihedral is formed by its main side and the ground. The echo is strongest when the incident electromagnetic wave is along the normal direction of the dihedral. A high-resolution image corresponding to this aspect angle is formed by the proposed enhanced imaging method to increase the SCR of the target and improve the detection performance. Airborne FOPEN SAR data were used to validate the efficiency of the proposed method.