Alternative representation of dyadic Green's functions for circular cylindrical cavities with applications to the EMC characterization of space station modules

This paper compares two different representations of the dyadic Green's fun ctions for circular cylindrical cavities, also valid at the source point. T he representations are obtained by considering the cavity either as a circu lar waveguide (longitudinal representation) or as a radial waveguide (radia l representation), terminated by conducting surfaces. The radial representa tion of dyadic Green's functions for circular cylindrical cavities is not a vailable in the previous literature and is applied to study the field penet rating a space station module through apertures, including lateral ones, or due either to elementary sources or to wire antennas active in the module. We show that for the typical dimensions of spatial modules the radial repr esentations give rise to more convergent series and therefore are more suit able for the computation of the cavity electromagnetic fields. The problem of obtaining the self and mutual impedances of two wire antennas located in the cavity is also discussed in general, and various results are reported for particular cases. Simplified cavity models can be effectively applied t o the electromagnetic compatibility (EMC) characterization of space station modules.