基于电磁计算理论的雷达成像仿真研究

A Study on Radar Imaging Simulation Based on Electromagnetic Calculation Theory

逆合成孔径雷达在战场监测、导弹突防等方面有着广泛的应用。文中采用电磁计算理论研究雷达成像仿真技术。首先,采用物理光学法得到目标表面电流,计算目标大带宽、多角度范围内散射特性。针对计算量大、耗时长的缺陷,文中采用最佳一致逼近理论拟合出目标在大频带、多角度范围内的散射特性,通过计算验证,在不影响精度的前提下大大提高了计算效率;接着,利用计算得到的散射数据,构建宽带目标回波信号,利用转台理论,进行小角度内的距离-多普勒成像;最后,以锥台为例,计算了从不同角度入射时的目标雷达图像,可以验证该方法的正确性和高效性。

Inverse synthetic aperture radar has wide applications in the fields of the battlefield surveillance, missile penetration. The radar imaging simulation is studied employing electromagnetic calculation theory in this paper. Firstly, the target surface current is obtained using the physical optics method, and the scattering characteristics in a wide bandwidth and multi-angles are calculated. In order to solve the defect of large amount of calculation and long time consuming, the best uniform approximation is adopted to fit the scattering characteristics in a wide bandwidth and multi-angles. The calculation efficiency is greatly improved without affecting the accuracy. Then, the wideband target echo data are constructed by using the calculated scattering data, and then we can obtain the range-doppler imaging in small angle using turntable theory. Lastly, taking the cone platform as an example, the radar image of the target from different angles is calculated, which shows validity and high efficiency of this method.