Antenas de microfita sobre substratos dielétricos anisotrópicos e ferrimagnéticos magnetizados.

Abstract

This work presents a theoretical and numerical analysis of the parameters of a rectangular patch microphyte antenna whose substrates are composed of magnetized anisotropic and ferrimagnetic dielectric materials. For this, we use the Hertz potentials method in the spectral domain in combination with the moment method to determine its characteristics, such as: resonance frequency of isolated and coupled patches, quality factor, radiation diagrams. and input impedance. The analysis uses the definition of the Hertz vector potentials which, together with Maxwell's equations and boundary conditions, allow the expression of field components as a function of the current density components in the patch. The moment method is applied, generating a matrix equation whose solution is the complex resonance frequency and the quality factor. Once these parameters are determined, the principles of electromagnetic theory are used so that other characteristics can be determined. Thus, the stationary phase condition is used to determine the radiation diagram from the tangential field components in the spectral domain. The quality factor is calculated using a relationship between the real and imaginary parts of the frequency of resonance and the moment method and applied to obtain the impedance of considering the effect of coaxial cable power. Initially, multi-layer microphyte antennas and uniaxial anisotropic dielectric overlays are considered, taking the optical axis in the three main directions of the Cartesian coordinate system. Then, the analysis of rectangular patch microphyte antennas with magnetized ferrimagnetic layers is performed, considering the same three directions described above for the magnetization field. In the work, numerical results are presented for the quantities involved, that is, the resonant frequency, the quality factor, the radiation diagram and the input impedance. Comparisons are made with other results presented in the literature, and in some cases these comparisons consider only the particular case of isotropic materials, corresponding to the situations encountered available in the literature. In these situations, convergence is done under the boundary condition. where the permittivity or permeability of the material behaves as that of an isotropic material. Suggestions for continuity of work are also presented.