The Analysis Of Microstrip Array Antennas Using The Spectral Domain Method

As a Planar stratified structure, excellent properties of microstrip antennas stimulate more and more array antennas to select them as array elements. This article is basing on the planar layered medium model, using the spectral domain approach for the accurate analysis of array antenna’s electromagnetic properties.Firstly, the article applies the mature transmission line theory to obtain spectral domain Green’s function in the mixed potential form completely and the singularity characteristics of spectral domain Green function are introduced. Then according to the exsiting wave in the planar stratified structure, these wave fitting effect of using the discrete complex image method(DCIM) and rational function fitting method(RFFM) is studied, proposing a solving method which combines DCIM with RFFM. Compared with the method based on the DCIM, it don’t need the cumbersome poles lookup and compared with the RFFM, it can accurately fit the quasi-static items,So the computational efficiency and accuracy of this method are improved. In order to verify the accuracy of the method, the calculating result of the double medium layer results which are compared with the literature, are in good agreement. Additionally, this article briefly describes the method of moments(MoM) of the basic steps, and by analyzing the scattering and radiation in the stratified media, it will be extended to adapt to the question of layered media. Then the article studies the basic two-dimensional p-FFT processes and applies it for the analysis of a typical electromagnetic scattering model, validating accuracy and effectiveness of the two-dimensional p-FFT algorithm. Finally, scattering and radiation performance of the array antennas in the different feeding type, microstrip phased array scanning characteristics and mutual coupling extraction and the influence of multilayer dielectric antenna cover is analysised in the proposed method. Calculated results with commercial software FEKO simulation results comparing good agreement proves the validity of the proposed method.