Campi Elettromagnetici - Articolo funzione di Green

Spectral dyadic Green’s function formulation planar integrated structures

1057 IEEE Transactions 36, no. 8, on antennas and propagation, vol. August 1988 for

More realistic model of the excitation of the integrated Abstract—The dyadic Green’s function, transformed in the Fourier a planar integrated structure domain, is evaluated in the general case of structure must take into account, in a correct way, the fed by distribution of tridimensional electrical sources arbitrarily a presence of tridimensional sources, generally located in the the basis located in the dielectric substrate.

The analysis is carried out on layers. Moreover, it should be pointed out that the vertical of the Maxwell’s equations written for the time variation and e)*‘ component of the feeding source has a relevant influence in the transformed in the Fourier domain.

The elements of the spectral dyadic evaluation of the losses of the structure and on the radiation Green’s function are evaluated via the transmission-line analogy by making of very general equivalent circuits of the planar structure use pattern. determined for the case of transverse electric (TE) and transverse Only recently some examples of study of microstrip a(TM) magnetic waves according to general tridimensional source structures based on the spectral analysis have appeared in excitation.

General properties among the elements of the Green’s technical literature. The first paper dealing with the full wave function are obtained, due to the electrical and geometrical symmetry of the structure, and the different roles played by the independent terms of approach concerning the aforementioned problem was pre-are the matrix discussed.

An expression for the power produced by the 121,sented by Itoh in where the evaluation of a partial set of [sources, evaluated through its spectral power density, is derived, and the the dyadic Green’s function is obtained under the hypothesis of formal representations in the Fourier domain of the input impedance for planar sources located at the interface.

However, the study is vertical and transverse sources are presented. mainly focused on the eigenvalue problem of the structure,

Introduction

I. and limited interest is given to the radiated fields. Papers oriented in the study of tridimensional feeding sources can be It is well known that microstrip integrated circuit [19], [20] found in where the theoretical approaches are (MIC) antennas are now largely used in the microwave and different from the full wave theory.

Recently, Chi and millimeter wave frequency bands due to their intrinsic [21] presented a paper dealing with the radiation Alexopoulos advantages with respect to the mo