雷达目标三维成像算法研究

逆合成孔径雷达三维成像技术可有效揭示雷达目标散射源的空间分布;相比于传统的距离向和方位向二维成像,三维成像又增加了俯仰向的分辨能力,可以识别雷达目标高度方向的散射源分布情况。从雷达目标回波信号分析出发,探讨了三维成像的基本公式及算法。距离向分辨采用传统的FFT(快速傅里叶变换)实现,方位向和俯仰向分辨运用卷积反投影算法实现。讨论了两种实现方位向和俯仰向成像的投影插值算法,即二维投影插值法和直接投影法,与传统的二维投影插值算法比较,直接投影法具有计算速度快和计算精度高的优点。

Research on Three-Dimensional Imaging Algorithm of Radar Target

Three-dimensional inverse synthetic aperture radar（ISAR） imaging can effectively reveal the spatial distribution of radar targets; compared with the conventional two-dimensional imaging, which only in- volves the resolution in range and azimuth directions, three-dimensional imaging adds the resolution in eleva- tion direction. Based on an analysis of the echo data from radar targets, the basic formulas and algorithm of three-dimensional imaging is discussed. The range image is obtained by the traditional fast Fourier transform （FFT） algorithm, while the azimuth and elevation images are obtained by the convolution back projection （CBP） algorithm. Two algorithms for realizing azimuth and elevation projections are presented, i. e. , two- dimensional projection interpolation method and direct projection method. Compared with the two-dimension- al projection interpolation method, direct projection method is faster and has higher accuracy.