The physical processes in a waveguide-dielectric structure

The physical processes occurred in the waveguide-dielectric structure that has the form of a section of rectangular cut-off waveguide with dielectric insertion, which completely fills the cross section of the waveguide have been considered. The electromagnetic fields in the classic waveguide-dielectric resonator without devices for its excitation and a coupling element with two sections of the cut-off waveguide have been calculated. The expressions for the reflection and transmission coefficients of the structure under consideration are presented. The positions of poles and zeros of the reflection coefficient have been investigated with a fractional-rational approximation and they have been compared with the natural frequencies. The obtained results are useful for measuring the properties of dielectric materials with the aid of waveguide methods.