INVESTIGATION OF MICROWAVE DIELECTRIC - RESONATOR FILTERS
Abstract
The effect of metal-wall proximity on resonant frequency and unloaded Q of a dielectric resonator is considered. It is shown that nearby walls, such as those of a surrounding nonpropagating waveguide, raise the resonant frequency and degrade the unloaded Q. A rigorous solution to the problem is not feasible, and therefore an approximate analytical approach based on the proximity of a single infinite plane metal wall is proposed instead. The effect of the wall on resonant frequency is computed first. Then a perturbation method is applied to obtain a formula for the Q of the resonator loaded by the dissipation loss on the metal wall. Next the shift in resonant frequency and the unloaded Q of a resonator in a rectangular waveguide are obtained by superimposing the effects of the individual four walls. A comparison of calculated and measured data shows good agreement in the transverse-orientation case. However, agreement in the axial-orientation case is poor. It is indicated that certain sources of error tend to cancel in the transverse case, while adding in the axial case. Further discussion of the axial case will be given in the next quarterly report. The results of further investigation of band-stop filters in TEM line are contained in this report.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 27, 1965
- Accession Number
- AD0465668
Entities
People
- Eugene N. Torgow
- Seymour B. Cohn