Dielectric Waveguide Resonator Research Articles

Miniaturized Dual-Band Filter Using Dual-Mode Dielectric Waveguide Resonator

This letter presents a novel miniaturized dual-band bandpass filter (BPF) using a dual-mode dielectric waveguide resonator (DWR). The DWR is a cylinder dielectric block with the surface being silver-coated. The two modes are TM010 and TM011 modes, which are used to construct the two passbands. The frequency of them can be adjusted by changing the radius and the height of the cylinder DWR and the frequency space can be controlled independently. The BPF is composed of three cylindrical cavities, which are arranged in an equilateral triangle. The three cavities construct a cascaded trisection (CT) unit, which creates a transmission zero (TZ) at the upper side of the two passbands. Finally, a dual-band BPF using DWR is simulated, manufactured, and measured to exhibit the feasibility of the proposed design. Their results are in good agreement, showing good performance, such as miniaturization, good return loss (RL), and upper stopband selectivity.

Design of high-gain wideband substrate integrated waveguide dielectric resonator antenna for D-band applications

The emerging mobile broadband applications and services demand high-performance networks operating at high frequencies. There is need for high gain and wideband antennas for mobile equipment to support high-speed communications in the millimeter (mm) wave and terahertz (THz) frequencies. In this paper, we propose a wideband substrate integrated waveguide (SIW) fed dielectric resonator antenna (DRA) for D-band applications. A rectangular dielectric resonator element is designed to operate in higher order modes. Wideband operation is achieved by merging adjacent resonances of the different modes. We present a systematic and sequential application of impedance matching techniques to merge the passbands of a multi-mode dual-band DRA, to achieve a wideband response. The proposed design operates between 123.97 GHz and 152.13 GHz. This represents a -10 dB bandwidth of 20.39% at the center frequency of 138.05 GHz. The proposed antenna design has stable broadside radiation patterns, exhibiting a high gain of 11.67 dBi, directivity of 13.36 dBi and maximum total efficiency of 79% . The proposed design is suitable for future generation wireless communication in the terahertz band.

Dual-Mode Dielectric Waveguide Monoblock Filter Design

This paper presents a design of dielectric waveguide filter using dual-mode dielectric waveguide resonators (DWRs). The filter is formed by a ceramic monoblock, thus it is compact and ease of fabrication. The employed degenerate modes of DWR are TE101 and TE011 mode, which can be coupled by a slot on the dielectric block. The coupling between a dual-mode DWR and a single-mode DWR is realized by aperture and slot. The external coupling is realized by a silver-coated blind hole that aligns to the mode for excitation. Transmission zero (TZ) can be flexibly generated above or below passband, by changing the relative position of coupling slot. A sixth order bandpass filter working at 4.9 GHz is designed using dual- and single-mode DWRs. The filter is fabricated and measured, agreeing well with simulation. This filter has compact size, low insertion loss, good selectivity and wide spurious-free response, which is applicable to 5G base stations.

Integrated-Designs of Filtering Circuits Based on Adjustable Dielectric Waveguide Resonators

This brief presents a new kind of adjustable dielectric waveguide resonator (DWR), based on which integrated designs of filtering circuits are conducted. The DWR is composed of a dielectric part as the main resonating body and a printed circuit board (PCB) part as the cover. An unmetallized blind hole is carved at the upper surface of the dielectric part. A tuning screw is installed on the PCB and inserted into the unmetallized blind hole to adjust the resonant frequency the DWR. This adjusting method is flexible and reversible. By using the proposed adjustable DWR, a fourth-order bandpass filter (BPF) is designed, fabricated and measured. The measured results show that the BPF is with an in-band insertion loss of 0.8 dB and an in-band return loss better than 19 dB. A capacitive cross coupling structure is constructed on the PCB so that two transmission zeros are introduced close to the passband to improve the filtering selectivity. In addition, a Wilkinson power divider is realized on the PCB and integrated with the above BPF, forming a filtering power divider. The measured in-band insertion loss of the filtering power divider is 1.1 dB. The isolation is better than 24 dB and the maximum phase imbalance is 1° in the passband.

Circular cross‐coupling dielectric waveguide filter based on 90‐degree sectoral resonators

AbstractIn this study, a circular cross‐coupled dielectric waveguide (DW) filter was realized based on 90‐degree sectoral resonators. The filter is formed by splicing four 90‐degree sectoral DW resonators (SDWRs). A shallow blind hole (BH) was set at the center of each 90‐degree SDWR to adjust the resonant frequency. The magnetic coupling between the resonators was realized through the rectangular wall and shallow BH. Electrical coupling between the resonators was achieved through deep BHs. The overall structure was designed, simulated, and fabricated. The measured results demonstrate that the designed filter has a center frequency of 3.6 GHz, bandwidth of 200 MHz, insertion loss less than 1 dB, in‐band return loss greater than 15 dB, and two out‐of‐band transmission zeros at 3.38 and 3.82 GHz.

Low‐loss filtering switch by using dielectric waveguide resonators

A low-loss filtering switch by using the dielectric waveguide resonators (DWRs) is proposed. It is composed of a dielectric part and a printed circuit board (PCB) part, which are electrically connected by soldering. The filtering function is mainly implemented by the coupled DWRs and the switching function is realized on the PCB by simply changing the resonant frequency of the DWR. A fourth-order filtering switch, in which two DWRs are designed to be switchable, is designed for verification. When the PIN diodes are turned off, the filtering switch is on and an excellent bandpass response is obtained. No extra loss is caused by the off-state PIN diodes. When the PIN diodes are turned on, the resonant frequencies of the two switchable DWRs are moved away so that the filtering switch is off. Then, the designed filtering switch is fabricated and measured. The simulated and measured results exhibit excellent accordance. In on-state measurement, the passband is from 3.5 to 3.6 GHz and the in-band insertion loss is as low as 0.8 dB. Nevertheless, the proposed design owns much lighter weight since no metal cavity is used. In the off-state measurement, the isolation is better than 36 dB.

Bloch wave concept: transmission line model based on protein polarized dendrites treated as dielectric waveguide resonator

Nowadays, the physical analogy in biology has become a desirable research domain for academics. Here, we discussed many exciting features regarding the biological system that could help us to understand the underlying mechanism inside it. This manuscript focuses on the soliton/Bloch wave concept along with the periodic active protein polarized dendrite. The velocity of the existent soliton wave is identified by considering the transmission line model of protein polarized dendrite as a dielectric waveguide. This paper aims to understand and explore the mechanisms of biological rhythms and the role of neural oscillations and synchrony in information processing.

FOCUSING OF MODES WITH AN INHOMOGENEOUS SPATIAL POLARIZATION OF THE DIELECTRIC RESONATOR OF A TERAHERTZ LASER

Wave beams with non-uniform spatial polarization of radiation are necessary for solving important fundamental and applied problems related to the interaction of electromagnetic waves of the terahertz range with matter - surface diagnostics of materials, thin films, biological objects, information transmission, and processing systems, achieving subwave resolution in tomography, communication systems, etc. The results are presented in the literature on focusing on pulsed radiation beams in the terahertz range. Data on the focusing of continuous radiation beams are practically absent. The spatial-energy characteristics of laser beams having an inhomogeneous spatial polarization at their moderate and sharp focusing are theoretically investigated. As the radiation understudy, in the numerical simulation of the focusing of wave beams in the terahertz range, we used the modes of a laser waveguide dielectric resonator that coincide with the eigenmodes of a hollow dielectric waveguide. Symmetric and asymmetric modes with both spatially inhomogeneous azimuthal, radial, and homogeneous linear field polarizations are studied. The components of the electric field of laser beams during their propagation in free space were studied using the Rayleigh-Sommerfeld integrals in the nonparaxial approximation. The effect of the focusing lens on laser radiation was taken into account using the amplitude-phase correction function. The distributions of the total intensity of the resonator modes and their individual field components in the focal region of the lens are studied. The obtained results expand the knowledge about the features of focusing terahertz laser beams.

Фокусировка неоднородно поляризованных мод лазерного волноводного диэлектрического резонатора

Фокусировка неоднородно поляризованных мод лазерного волноводного диэлектрического резонатора

Determination of refractive index and dielectric constant in the terahertz and microwave ranges

The results of measurements of the refractive index and dielectric constant of several samples of porous materials in terahertz (THz) and microwave ranges are presented in the work. Such measurements are relevant, since porous materials have a wide variation of parameters and reference data do not reflect all their diversity.The permittivity of the materials was measured in the microwave range. The cylindrical waveguide-dielectric resonator on an evanescent waveguide was used. Measurements were made by two methods at frequencies of 10 ÷ 12 GHz. In one method, the investigated material was used as the dielectric element of the resonator. In another method, the dielectric element was made of fluoroplastic and the investigated material filled the evanescent parts of the waveguide. The accuracy of measurements was compared and the advantages and disadvantages of these methods were analyzed.The measurements were carried out in the THz range by a resonance method at a frequency of 890 GHz. A gas-discharge submillimeter laser with a wavelength of 337 μm was used for this purpose. The measuring device was a quasi-optical resonator with a smooth length adjustment. One of the mirrors of the quasi-optical resonator was simultaneously the output mirror of a submillimeter laser. The test material was placed in a quasi-optical resonator. The refractive index was determined from the change in the optical length of the resonator, when the investigated material was introduced into it.The difference in the measured parameters for the different materials studied correlates with the specific gravity of the materials. Significant changes in the parameters when changing the frequency have not been detected.The results of measurements can be used in the development of various devices with THz and microwave ranges, in particular, in the design of antenna fairings, dielectric waveguides, quasioptical elements, etc.

Измерение диэлектрической проницаемости пенопластов резонансным методом с помощью волноводно-диэлектрического резонатора

Измерение диэлектрической проницаемости пенопластов резонансным методом с помощью волноводно-диэлектрического резонатора

Свойства пере-страиваемого волноводно-диэлектрического резонатора миллиметрового диапазона с повышенной добротностью

Свойства пере-страиваемого волноводно-диэлектрического резонатора миллиметрового диапазона с повышенной добротностью

WAVEGUIDE-DIELECTRIC RESONATOR OF THE MILLIMETER WAVE BAND

Specific features of the waveguide-dielectric resonator (WDR) operating in the millimeter wavelength band have been investigated. This paper considers the relation between the computed values of eigen frequencies and Q-factors of the H111-mode maintained in a WDR at a circular waveguide and the resonator parameters. The results of computations have been compared with the experimental data.

Selection of the higher transverse modes of a waveguide quasi-optical resonator

A method of spatial filtration for the selective excitation of individual higher-order transverse oscillation modes with a high degree of discrimination of undesirable modes in a waveguide quasi-optical resonator is described. The method is based on the use of a mirror with absorbing or scattering inhomogeneities discretely arranged on its surface. The efficient excitation of such modes in a waveguide dielectric resonator with a nonuniform amplitude-step mirror in the submillimetre wavelength range (at 0.4326 mm) is confirmed theoretically and experimentally.

Noncontact characterization of glucose by a waveguide microwave probe

We investigate the electromagnetic field interaction with a glucose aqueous solution using a microwave dielectric waveguide probe to evaluate the glucose concentrations. A microwave dielectric waveguide probe allows observation of the small variation of the glucose concentration changes in the range of 0–300mg/ml by measuring the change of the microwave reflection coefficient. We could observe the effect of concentration change of glucose with a detectable resolution up to 0.5mg/ml at an operating frequency of about f=2.0–2.5GHz. The change of the glucose concentration is directly related to the change of the reflection coefficient due to the electromagnetic interaction between the dielectric waveguide resonator and the glucose aqueous solution. The operational principal is explained by a plane-wave solution model. A glucose biosensor using a microwave dielectric waveguide probe provides a unique approach for glucose monitoring.

Photonic bandgap dielectric waveguide filter

The application of photonic bandgap (PBG) structures as the sidewall of the printed circuit board (PCB) dielectric waveguide filter is investigated. The effect of different PBG parameters on the Q-value of PBG dielectric waveguide resonator is evaluated. A PBG dielectric waveguide three-pole Chebyshev bandpass filter is realized. The measured performance matched well with the calculated results. The newly proposed I/O coupling structure makes the filter much easier for mass production.

Waveguide-dielectric resonator method for accurate measurement of parameters of materials at high frequencies

The theory is given, with an analysis and various examples, of the practical implementation of a method for measuring the relative permittivity ɛ*=ɛ′−iɛ″ of materials in the 0.5–26-GHz frequency range. The results and experimental errors are given of measurements of e′ in the range 2–200 and of tanδ in the range from 5·10−5 to 2·10−2.

Resonant frequency and quality factors of a silver-coated λ/4 dielectric waveguide resonator

In this paper, resonant frequency, radiation loss, conductor loss, and dielectric loss of a silver-coated /spl lambda//4 dielectric waveguide resonator are investigated. Leakage of the electromagnetic field from the open-end face of the resonator is the only source of radiation, which also affects the resonant frequency. New theoretical expressions are devised to calculate resonant frequency, conductor quality (Q) factor, dielectric Q factor, and radiation Q factor. Effective conductivity of the silver-coated resonator is estimated from experimental unloaded Q factor. The theoretical analysis is validated by the experimental result and the data obtained using the finite-difference time-domain (FDTD) technique. Finally, we have designed and fabricated a dual-mode bandpass filter using this resonator.

Eigen electromagnetic oscillations in the waveguide-dielectric resonator with two-layer filling

The method of the solution problem on the eigen oscillations spectrum of electromagnetic field in the waveguide-dielectric resonator with the two-layer dielectric element was presented. The numerical calculations of the resonance frequencies for theHE 111-,E 011- andH 011-oscillations types in the investigated structure were performed. The calculation results were correlated with experimental data.

Quasi‐analytical method for analysis of multisection waveguide structures with step discontinuities

In this paper an effective quasi‐analytical field theory method for the analysis ofmultisection rectangular waveguide structures with E or H plane step discontinuities is presented. A version of Galerkin's method is used to solve the corresponding diffraction problems. The weghted Gegenbauer polynomials are used as basis functions, taking into account the field asymptotic at the discontinuity edges. Another important feature of the solution is the separation and analytical transform of the matrix operator static part of the obtained linear algebraic equations set. The method proposed here guarantees rapid convergence and high accuracy of the numerical results. It has been verified by numerical convergence investigation and comparison with the results of other works. The method can be applied for the effective design of a wide range of passive waveguide components: different band‐pass, stop‐band, and low‐pass filters, waveguide phase shifters, polarizers, etc. As examples of the concrete devise design, the characteristics of the inductive and capacitive iris filters, evanescent‐mode waveguide dielectric resonator filter, and E plane stub‐loaded, fixed‐phase shifter are given in the paper.