基于ASM-MBF的阵列互耦补偿方法

目的解决传统矩量法在分析阵列互耦时存在未知数过多、计算慢的问题。方法研究一种结合宏基函数思想和无限阵列近似的,可用于大型阵列的互耦分析方法——ASM-MBF,通过构建MBF高阶宏基函数,来缩减矩量法计算时产生的矩阵规模。为减小大型阵列的单一激励电流分布的求解难度,利用无限阵列的单一激励电流分布进行近似分析,并且通过阵列扫描法(ASM)进行求解。将其结果和已经得到广泛使用的RWG-MOM计算结果进行对比,随后在ASM-MBF方法的基础上,求解得到阵列的互阻抗矩阵,并用互阻抗矩阵对传统的不考虑单元间互耦的阵列综合问题进行补偿修正。结果随着单元上MBF的个数的增加,RWG-MOM方法与ASM-MBF方法的计算结果的误差逐渐降低,在单元上MBF数目为4的时候,两种方法的误差仅为-140 dB,而此时ASM-MBF法未知数数量仅为RWG-MOM法的5%。在阵元间距不同的情况下,所使用的互耦补偿方法均取得优良的补偿效果,尤其在间距较小,互耦的影响较大时,补偿后的方向图已十分接近理想情况。结论ASM-MBF方法可以在考虑精度的同时实现矩阵降阶,使用该方法计算得到互阻抗矩阵,可对传统的不考虑单元间互耦的阵列综合问题进行有效补偿。

Array Mutual Coupling Compensation Method Based on ASM-MBF

The work aims to solve the problem that the MoM has too many unknowns and slow calculation in the analysis of array mutual coupling. A mutual coupling analysis method-ASM-MBF which combines macro-base function and infinite array approximation and can be used in the large array was studied. By constructing the MBF high-order macro-base function, the matrix size generated by MoM was reduced. In order to reduce the difficulty of solving the single excitation current distribution of large arrays, the single excitation current distribution of the infinite array was used for approximate analysis and the solution was made by array scanning method (ASM). The results were compared with that calculated by widely used RWG-MOM. Then, based on the ASM-MBF method, the mutual impedance matrix of the array was obtained. The mutual impedance matrix was used to compensate the traditional array synthesis problem without considering mutual coupling between cells. With the increase of the number of MBF on element, the error of the calculation results of RWG-MOM and ASM-MBF was gradually reduced. When the number of MBFs on the unit was 4, the error of the two methods was only -140 dB. At this time, the number of unknowns by ASM-MBF was only 5% of that by RWG-MOM. In case of different element spacing, the mutual coupling compensation methods used achieved excellent compensation effects. Especially when the spacing was small and the influence of mutual coupling was large, the compensated pattern was very close to the ideal situation. The ASM-MBF method can achieve matrix reduction while considering accuracy. Calculating the mutual impedance matrix by this method can effectively compensate the traditional array synthesis problem without considering mutual coupling between cells.