INVESTIGATION OF MICROWAVE DIELECTRIC-RESONATOR FILTERS
Abstract
Research concerns a study of the feasibility of high-dielectric constant materials as resonators in microwave filters. First- and second-order analyses of dielectric resonators are given for rectangular and cylindrical shapes. The first-order solution assumes the surface of the dielectric resonator to be an open-circuiting wall, while the second-order solution assumes boundary conditions that are more complex, yet subject to simple computation. The superiority of the second-order solution is shown by comparison of theoretical and experimental resonant-frequency data. However, a frequency discrepancy of about 10 per cent indicates that either the second-order solution requires further improvement, or that the assumed dielectric-constant value is in error, or both. Resonant frequency and unloaded Q measurements were made on six cylindrical samples having a wide range of diameter to length ratios. The experimental techniques are described. The unloaded Q of six TiO2 samples was measured and found to be about 7000 at S-band. Since these samples were not of the highest purity, even higher Q's should be possible. The effect of waveguide wall proximity was studied experimentally, and curves are given showing the effect of sample position in the waveguide on resonant frequency.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1963
- Accession Number
- AD0426201
Entities
People
- C. W. Chandler
- S. B. Cohn