改进型四波束Butler矩阵的幅度加权

Amplitude Weighting of Modified Four Beams Butler Matrix

在4×4Butler矩阵基础上,在保持波束数目和指向不变的情况下,通过增加4个功分器和4个180o移相器,对矩阵进行改进。将天线阵列扩展为8单元线阵,并对改进后的矩阵进行近似切比雪夫分布幅度加权,仿真结果表明加权后副瓣电平明显改善,最后对半功率覆盖范围和波束交叉电平的影响进行分析。

Through adding four power dividers and four 180^. phase shifters, the 4×4 Butler matrix is modified while the number and direction of beams are steady. The antenna array is expanded to eight units linear array, and the amplitude weighting which approaches Chebyshev distribution is applied to the modified matrix. The results of simulation show that the side lobe level of weighted matrix is improved markedly. Finally, the influence of half power coverage and cross level of beams are analyzed.