Analysis of Substrate Integrated Waveguide Structures Based on the Parallel-Plate Waveguide Green's Function

Analysis of Lossy Siw Structures Based on the Parallel Plates Waveguide Green's Function

“…Following the notation in [14], the dyadic Green's function is expressed in the spectral domain as a series of cylindrical wave functions…”

“…However, as is known, vias are made of good conductor and one can consider that they scatter mostly TM (TE ) field when the impinging field is TM (TE ) and that the TE (TM ) field is negligible. Under this hypothesis the scattering from metallic vias is taken into account as in [14] but enforcing the following boundary conditions on the cylinders surface:…”

“…In [10] the Boundary Integral Resonant Modes Expansion (BIRME) has been adapted to analyze efficiently post walled structures, in [11][12][13] SIWs have been analyzed considering only the presence of the parallel plate waveguide (PPW) TEM mode and taking into account the scattering by the metallic posts, so reducing the analysis to the solution of a two dimensional problem. In [14] the authors presented a technique based on the full dyadic Green's function of the parallel plate, expressed as series of vector wave functions [16] TE and TM with respect to the waveguide height. In this last case also, the presence of the metallic vias was included in the analysis solving the scattering problem.…”

“…The method was also used to determine the characteristics of SIW resonators [17] and to analyze SIW based slot arrays [18]. In this paper we present the extension of the technique presented in [14], which treated only lossless case, to lossy structures. To evaluate the power dissipated on the metallic surfaces and in the dielectric slab, the dyadic Green's function is changed to take into account the finite conductivity of the metallic plates [19] and including the dielectric losses into the argument of the wave functions.…”

“…The complete derivation of the Green's function has been given in [14] but in this paper a slightly different path starting from the lossless case in [14] and relying on [15] is followed. The scattering by the lossy metallic cylinder, is considered later and added to the contribution from PPW.…”