三维大型任意阵列宽带波束指向性图的快速计算

为解决常规频域直接方法计算大型三维阵列宽带波束图(BP)速度较慢,无法满足大型三维宽带阵优化设计需求的问题,提出了一种适用于大型三维任意阵列的宽带BP图的快速算法.在利用二维非均匀快速傅里叶变换(NUFFT)伴随操作实现二维阵列BP频域快速计算方法的基础上,引入第三空间频率变量,将与阵元纵向坐标有关的相位因子转化为第三...

Fast computation of wideband beam pattern of large three-dimensional arbitrary arrays

In order to solve the problem that computation of wideband Beam Patterns(BPs) of large three-dimensional(3-D) arrays is too slow to meet the requirements of designing large array using the conventional frequency-domain Direct Method(DM),a fast method is proposed for computation of wideband BPs of large 3-Darbitrary arrays.Based on the previous frequency-domain methods of computing wideband BPs of 2-D arrays using 2-D Nonuniform Fast Fourier Transform(NUFFT),the proposed method applies 3-D NUFFT as well as nonlinear interpolation to realize fast computation of wideband BPs of 3-D arrays,in which the third space frequency variable is brought in by conversion of the phase term related to the vertical coordinate of 3-D arrays.The minimum number of divisions of spatial frequency is theoretically deduced to meet the accuracy requirements of BP interpolation.Theoretical analyses show that computational cost of the proposed method is reduced by about one order of magnitude compared with the conventional DM,while keeping the computational error around 1%.Simulations are conducted to verify the theoretical conclusions.The proposed method makes it possible to design large 3-D wideband arrays by using optimizing algorithms which need massive iterations.