Tunable dielectric resonator with circumferentially magnetized ferrite disks
Electronically tunable dielectric resonator containing circumferentially magnetized ferrite elements has been investigated. The structure of the resonator has been analysed to obtain the optimal parameters. The resonator was constructed whose resonant frequencies can be switched by short current pulses between two stable values that differ in frequency up to 25 MHz with Q-factor value about 4200.
Magnetic tuning of cylindrical H/sub 01 delta /-mode dielectric resonators
The theory of magnetic tuning of cylindrical H/sub 01 delta / dielectric resonators is developed. It is based on rigorous solutions to the dielectric resonator systems containing microwave ferrites. It is shown that the most effective magnetic tuning of H/sub 01 delta / dielectric resonators can be accomplished by inserting a thin ferrite rod through an axial hole in the resonator. This kind of tuning utilizes the dependence of the parallel permeability tensor component mu /sub z/ on the magnetic field applied. Experiments have been performed which show that a 4% tuning range can be attained with a Q-factor of the resonant system of the order of 2000 at X-band. Using an appropriate DC magnetic field circuit, a 120 MHz tuning bandwidth has been obtained with a consumption of tuning power of about 75 mW. >
Properties of shielded cylindrical quasi-TE/sub 0mn/-mode dielectric resonators
Comparison of the Rayleigh-Ritz method and the mode-matching method for computations of quasi-TE/sub 0mn/-mode frequencies and unloaded Q-factors of shielded dielectric resonators is presented. Rigorous bounds for the true quasi-TE/sub 0mn/-mode frequencies are assessed. Influence of various parameters on the resonant frequencies, unloaded Q-factors, and the temperature coefficients of the resonant frequency is demonstrated for many shielded dielectric resonator structures. Different approaches to unloaded Q-factor computations are discussed and numerically compared. >