Система соосных дисковых диэлектрических резонаторов с азимутальными колебаниями

Abstract

The own q-factor of a disk dielectric resonator (DDR) with azimuthal oscillations is determined by the radiation losses from the disk surface and dissipation in the dielectric. A change of disk parameters reducing the influence of one of these factors invariably causes an increased influence of the other parameter, whereas the own q-factor does not exceed 1/tgδ of the disk material. In a resonant structure made in the form of two coaxially arranged disks, the q-factor may be several times higher than this value. That the effect is in principle possible is obvious: in a multilayer structure with different dissipation in layers, it is possible to localize the electromagnetic field in an area with low dissipation. Preliminary experimental studies have shown that the effect does take place and depends on the choice of the working type of azimuthal oscillations and system parameters. The aim of this study is to justify the choice of the type of azimuthal oscillations and the region of structural parameters with which the highest levels of the own q-factor are obtained. For calculating the characteristics of azimuthal waves of the HE- and EH types producing oscillations in the DDR system, the phenomenological method of effective dielectric permeability was used. A system of distributed coupled planar dielectric waveguides and a dielectric cylinder were considered as the method’s first and second models, respectively. The results from an analysis of dispersion and energy characteristics of the own types of azimuthal resonators have shown that the highest levels of own q-factors are characteristic of an even EH-type and can be several times higher than 1/tgδ.