一种快速星载合成孔径雷达波束优化算法

A fast beam optimization algorithm of spaceborne SAR

针对星载合成孔径雷达(SAR),提出了一种快速的波束优化算法。该方法以快速傅里叶变换(FFT)为基础,对星载SAR的波束进行赋形,并压制了模糊区。利用快速傅里叶逆变换(IFFT)快速计算出方向图,然后和期望的方向图进行比较,对不满足期望方向图的区域,直接用期望方向图的值代替。重复上述操作,直到方向图满足设计要求。和原有的波束优化方法相比,该方法不做各种复杂操作,因而大大节省了优化时间,提高了速度。两个仿真结果都表明该方法实用、高效。

In this paper,a fast beam optimization algorithm for spaceborne Synthetic Aperture Radar（SAR）is proposed. By using this algorithm, the beam of spaceborne SAR antenna is optimized, and the ambiguity areas are depressed. Firstly, the complex value of the array pattern is obtained by using an inverse Fast Fourier transform（IFFT）. Then compared to the desired pattern, all the values of the pattern exceeding the desired pattern are replaced by the values of the desired pattern. Repeat the above operation until the array pattern satisfies the pattern requirements. Compared with the conventional methods, the proposed algorithm needs no complicated operation. Therefore, it provides significant improvements in terms of computational speed and optimization time. Two examples are presented to demonstrate the high efficiency and practicality of the method.