Ferrite Tuned Dual-Mode Dielectric Resonator Filters (original) (raw)

Tunable dielectric resonator bandpass filter

13th International Conference on Microwaves, Radar and Wireless Communications. MIKON - 2000. Conference Proceedings (IEEE Cat. No.00EX428)

A simple but efective technique has been applied to magnetically tune the quasi-TEoll mode dielectric resonators. The tuning was achieved by means of the fkrrite rod situated centrally in the dielectric resonator and extending over the shield The fkrrite parameters were changed by DC magnetic field. The method assures the high quality factor of the resonator, over 3.4% tuning range and suflcientb good spurious response. The tuning has been achieved by means of the ferrite rod situated centrally in the dielectric resonator and extending over the shield to the electromagnet system. The ferrite parameters were changed by DC magnetic field produced by the DC current. The method assures the high quality factor of the resonator, 3.4% tuning range and quite good spurious resppnse. Measured filter characteristics show low insertion loss 0.32 + 0.65 dB and excellent retum loss better than 30 dB at center frequency in the full tuning range.

Design and Realization of the High-Q Triple Dielectric Resonator Filters with Wide Tuning Range

29th European Microwave Conference, 1999, 1999

A triple dielectric resonator designed for a wide tuning range is introduced. The structure is analyzed by the radial mode matching method. A single resonator filter optimized for the wide tuning range, constant unloaded quality factor and improved spurious characteristic is presented. Over 26% timing range has been achieved with the insertion loss of 0.61-0.27 dB and 3 dB fllter bandwidth of 5.15 t 0.95 MHz while the unloaded quality factor remained nerly constant

Dual-mode dual-band conductor-loaded dielectric resonator filters

2017 47th European Microwave Conference (EuMC), 2017

A new class of dual-mode dual-band microwave filters is presented. Conductor-loaded dielectric resonators are used as a basic building blocks for these devices. The proposed resonator enables the realization of microwave filters with unloaded quality factors of 1000-4000 with good spurious performance and significant reduced size, e.g. less than the half physical size, compared to TEM filters. The basic properties of the proposed resonator have been studied and examined with the help of a finite element method solver (HFSS2015). A design example of a dual-mode dual-band bandpass filter with maximum transmission zeros for mobile communications is developed.

Miniature Triple-Mode Dielectric Resonator Filters

IEEE Transactions on Microwave Theory and Techniques

This paper presents a new class of triple mode dielectric resonator filters. These devices use dielectric-loaded cavities with unloaded Q-factor of 3000-5000 and reasonable spurious free window. The proposed structure is less than one quarter of the physical volume of TEM filters of the same Q. A finite element method solver for electromagnetic structures (HFSS) is used to study the main properties of this resonator. Fundamental design rules for a bandpass filter have been presented. A three pole bandpass filter was designed, fabricated and measured to verify the proposed approach.

Tunable dielectric resonator with circumferentially magnetized ferrite disks

2004

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.

Optimization of Spurious Response in Dielectric Resonator Tunable Filters

2006 International Conference on Microwaves, Radar & Wireless Communications, 2006

Methods of tunable filters spurious response improvement are described. Dielectric resonator based filters with ferrite elements suffer from spurious resonances located close to the useful passband. Optimization of the resonator structure as well as application of TEM resonators leads to significant improvement. Design methods and measured results are provided.

Experimental validation of analysis software for tunable microstrip filters on magnetized ferrites

IEEE Transactions on Microwave Theory and Techniques, 2005

Measurements are presented for microstrip filters on layered media containing magnetized ferrites. The measurements show that the filters can be tuned by adjusting the magnitude of the magnetic-bias field. The measured results are compared with full-wave numerical results obtained by the authors via the method of moments in the spectral domain. The agreement between experimental and numerical results is reasonably good. The results show that the bandwidth of the filters appreciably decreases as the tuning frequency increases for frequencies located above the magnetostatic waves range (MWR). However, tuning is achieved without substantial bandwidth reduction for frequencies located below the MWR.

Y-type Hexagonal Ferrite-based Band-Pass Filter with Dual Magnetic and Electric Field Tunability

This work is on the design, fabrication and characterization of a hexagonal ferrite band-pass filter that can be tuned either with a magnetic field or an electric field. The filter operation is based on a straight-edge Y-type hexagonal ferrite resonator symmetrically coupled to the input and output microstrip transmission lines. The Zn2Y filter demonstrated magnetic field tunability in the 8-12 GHz frequency range by applying an in-plane bias magnetic field H0 provided by a built-in permanent magnet. The insertion loss and 3 dB bandwidth within this band were 8.6±0.4 dB and 350±40 MHz, respectively. The electric field E tunability of the pass-band of the device was facilitated by the nonlinear magnetoelectric effect (NLME) in the ferrite. The E-tuning of the center frequency of the filter by (1150±90) MHz was obtained for an input DC electric power of 200 mW. With efforts directed at a significant reduction in the insertion loss, the compact and power efficient magnetic and electric...

Miniaturized Triple-Mode Bandpass Filter using Dielectric Resonators

2021 IEEE MTT-S International Microwave Filter Workshop (IMFW), 2021

This paper presents a compact triple-mode dielectric resonator bandpass filter based on a single waveguide cavity. Two barium titanate pucks are used in the design, placed in the middle of the metallic cavity to reduce the size of the filter. A third-order simplified Chebyshev bandpass filter is selected to verify the technique and simulated using HFSS software. The input and output coaxial probes are used to excite the degenerate EH11 modes, while the TM01 mode is excited using a vertical hole etched in the top of the barium titanate pucks. The resonator offers a size reduction ratio of about 15.6% compared with equivalent air-filled coaxial filters. The filter has finite transmission zeros on the high or low side of the passband.

The Effect of 2-Directional Magnetic Biasing Used for Tuning of a Ferrite-Loaded Re-entrant Cavity

IEEE Transactions on Nuclear Science, 2000

Cavities that are partially filled with ferrite material provide a tunable resonance frequency by making use of the changing µ-characteristics of ferrites when exposed to an external magnetic bias field. The concept of using either parallel or perpendicular magnetic biasing to reach a certain resonance frequency of a cavity has been known for many years. However, a cavity based on superposition of perpendicular and parallel magnetic fields to obtain improved ferrite characteristics was suggested in W. R. Smythe "Reducing ferrite tuner power loss by bias field rotation," IEEE Trans. Nucl. Sci., vol. 30, no. 4, pp. 273-275, 1983, but to our knowledge was neither tested nor built. Such a 2-directional biasing is expected to provide a reduction in RF losses for an identical tuning range as compared with the classical 1directional magnetic bias. We have successfully tested this theory with a measurement setup consisting of a ferrite-filled cavity, exposed to external biases that allow the clear separation of the two orientations of superposed magnetic bias fields. The outcome is an enlargement of tuning range with high cavity Ԛ and the possibility of fast tuning. In this paper, we describe the measurement setup and present the tuning ranges that we attained by applying different bias schemes.