基于MIMO-ISAR的弹道目标结构参数估计方法

传统的单站逆合成孔径雷达(inverse synthetic aperture radar, ISAR)成像为实现方位向的高分辨,往往会增大成像时间,但对于高速运动的弹道目标而言,此方法并不适用。针对这一问题,提出利用多输入多输出逆合成孔径雷达(multiple input multiple output ISAR, MIMO-ISAR)在空间上的多分布来达到时间上积累的效果。在得到多通道回波信号后,利用时频图和时间距离像对弹道目标锥顶散射点进行匹配。然后根据锥顶散射点信息对多幅ISAR像进行配准融合,得到一幅高分辨的融合ISAR像。最后利用不同雷达视线下的目标投影长度和目标几何参数之间存在的映射关系,反演出弹道目标的几何结构参数。通过仿真结果可以验证算法的有效性。

Estimating structural parameters of ballistic targets based on MIMO-ISAR

Traditional single-station inverse synthetic aperture radar (ISAR) imaging usually increases imaging time in order to achieve high azimuth resolution, but this method is not suitable for ballistic targets which have high speed. In order to work around this problem, it is proposed to use multiple input multiple output ISAR (MIMO-ISAR) multi-distribution in space to achieve the effect of time accumulation. After obtaining the multi-channel echo signal, the conical top scattering points of ballistic target are matched by time-frequency images and time distance images. Then, according to the cone top scattering point information, a superior resolution fusion ISAR image is obtained by registration and fusion of multiple ISAR images. Finally, the geometric parameters of the ballistic target are extracted by using the mapping relationship between the projection length of the target and the geometric parameters of the target under different radar line of sight. The simulation results verify the effectiveness of the proposed algorithm.