RESONANT MODES OF STACKED CIRCULAR MICROSTRIP PATCHES IN MULTILAYERED SUBSTRATES CONTAINING ANISOTROPIC AND CHIRAL MATERIALS

Abstract

Galerkin's method in the Hankel transform domain (HTD) is applied to the fast and accurate determination of the resonant frequencies, quality factors and radiation patterns of stacked circular microstrip patches. The stacked metallic patches are assumed to be embedded in a multilayered substrate which may contain isotropic dielectrics, uniaxial anisotropic dielectrics, magnetized ferrites and/or chiral materials. For the case of stacked microstrip patches fabricated on isotropic dielectrics, the numerical results obtained for the resonant frequencies are compared with measurements carried out by the authors and with numerical results computed by means of the electromagnetic simulator "Ensemble". Good agreement is found among all sets of results. Original results are presented for the resonant frequencies of patches fabricated on anisotropic dielectrics and chiral materials, which show that substrate dielectric anisotropy and substrate chirality are not negligible effects. Finally, the results obtained for patches fabricated on magnetized ferrites indicate that the resonant frequencies of these patches can be adjusted over a wide range by means of the bias magnetic field, and that resonances cannot occur in the frequency region where magnetostatic mode propagation is allowed.