Efficient analysis of mutual coupling in periodic and non-periodic printed antenna arrays

Two techniques are explored for the efficient Macro Basis Functions (MBFs) analysis of large printed antenna arrays, including all the effects of mutual coupling. Both techniques can be applied after expressing the spatial-domain Green´s function in closed-form as a finite sum of cylindrical waves and one spherical wave. The first approach takes advantage of multipole decompositions and the second one consists of an interpolation technique for the reaction integrals between MBFs from very few sampling points. This reduced sampling is achieved after applying three physically based transformations to the contribution of each cylindrical or spherical wave to the reaction integral between MBFs.