基于孔径长度域重采样的快速恒定束宽波束形成

为解决宽带阵列天线波束宽度抖动的问题，在分析阵元权系数和阵列方向图傅里叶变换关系的基础上，提出了一种基于孔径长度域重采样的快速恒定束宽宽带波束形成方法。该方法通过期望方向图的傅里叶反变换获取孔径长度域上的权系数曲线，然后用不同的采样间隔对该权系数曲线进行重采样得到不同频率下的阵元权系数。由于仅需进行一次积分运算，该方法具有运算量小、速度快的特点。为使阵列方向图在恒定束宽的基础上具有更好的方向性，通过对孔径长度域拟合度的分析给出了期望方向图的设计方法。仿真结果表明所提方法可以快速形成方向性较好的宽带阵列恒定束宽方向图。

Fast constant beamwidth beamforming based on aperture length domain resampling

In order to solve the problem of beam width jitter for wideband array antenna,the Fourier transform relationship between weighting coefficients of the array elements and array antenna pattern is analyzed. Ac-cording to it,a novel fast constant beamwidth wideband beamforming method based on the aperture length do-main resampling is proposed. The weighting coefficient curve in the aperture length domain can be obtained by the inverse Fourier transform of the desired pattern. Then,weights of elements under different frequencies can be acquired by resampling the weighting coefficient curve. This method requires only once integral cal-culation,so it has the characteristics of small calculating amount and fast speed. To make the array pattern have bettter directivity on the basis of constant beamwidth,the design method of the desired pattern is pro-posed according to the analysis of fitting degree in the aperture length domain. Simulation results demonstrate that the proposed method can rapidly form the pattern with constant beamwidth and better direction.