To see the other types of publications on this topic, follow the link: Open cavity resonator.
Journal articles on the topic 'Open cavity resonator'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Open cavity resonator.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Nelin, E. A. "Resonator With Reflectors Based on Open-Circuited Stub." Visnyk NTUU KPI Seriia - Radiotekhnika Radioaparatobuduvannia, no. 98 (December 30, 2024): 66–72. https://doi.org/10.20535/radap.2024.98.66-72.
Full textAbstract:
Introduction. A two-stub resonator is considered as an analogue of a parallel resonant circuit. Another scheme of the resonator is similar to the Fabry-Perot optical resonator, formed by a resonator cavity and two reflectors. In the presented paper it is proposed a combined reflector formed by a stepped-impedance one and an open-circuited stub. Resonators with such reflectors have a higher quality factor Q than those known based on open-circuited stubs and than the Fabry-Perot resonator. 1 Half wavelength resonator. One of the analogues of the Fabry-Perot resonator is a half wavelength section of the transmission line. The Q-factor of such a resonator is significantly limited by the possible value of the section characteristic impedance. 2 Combined reflector. A combined reflector formed by stepped-impedance and reactive reflectors is considered. The conditions for the high efficiency of such a reflector have been established. One of the conditions corresponds to a large capacitance or a small inductance. Such properties have an open-circuited stub in the vicinity of resonance, respectively before and after it. 3 Reflector on open-circuited stub. The frequency characteristics of the reflector are considered. Stub reflectors of the resonator must differ in their reactivity. In this case, the length of one of the stubs is slightly shorter than the resonant length, and the other one is slightly longer than the resonant length. When detuning from the resonant frequency of the resonator, stub reflectors with different reactivity have amplitude and phase mismatches that increase with detuning. As a result, the Q-factor is greater than that of the Fabry-Perot resonator, whose reflectors are frequency-independent. 4 Comparison of the characteristics of the proposed and known resonators. Transmission responses of two variants of the proposed resonator and, for comparison, known resonators on open-circuited stubs are given. Resonators on stub reflectors have a much higher Q-factor. Characteristics of the proposed resonator and known half-wave resonators are compared. The proposed resonator has a higher Q-factor, and its transmission response has deep suppression bands due to stub’s resonances. 5 Formulas for Q-factor of resonators. An approximate formula for the Q-factor of the proposed resonator is given, which makes it possible to predetermine the value of the design parameters of the resonator. The formulas for the Q-factor of all considered resonators are summarized in a table. The approximate Q-values are close to the exact ones. 6 Resonators based on the inverted microstrip line. The proposed solution can be realized in resonators based on various transmission lines (planar, in particular microstrip, coaxial, etc.). The realization of the proposed resonators based on the inverted microstrip line taking losses into account is considered. The reduction in the Q-factor of the two variants of the proposed resonator due to losses is 2.5 and 5.5%. 7 Results discussion. Near the resonance, the frequency dependence of the reactive conductance of the open-circuited stub has a high steepness. Thanks to this, resonator based on such stubs is characterized by a high Q-factor and a steep transmission response. Near the passband, the stubs form two zeros corresponding to their resonances. In a two-stub resonator, the stubs are similar to the capacitance and inductance of the parallel resonant circuit. In the proposed resonator, where the stubs are reflectors, the frequency response properties of the two-stub resonator are preserved with a significant increase in the Q-factor. Conclusion. The efficiency of the considered resonator with reflectors on an open-circuited stub is three times higher than that of a traditional two-stub resonator. Due to the frequency dependence of the reflection coefficient of the reflector on an open-circuited stub, the increase in the Q-factor in the considered resonators is 51 and 25% compared to the Fabry-Perot resonator. As compared with known half-wave resonators, the proposed resonator has a higher Q-factor, and its transmission response has deep suppression bands due to stub’s resonances. The obtained approximate formula for the Q-factor of the resonator with stub reflectors makes it possible to predetermine the value of the design parameters of the resonator for a given Q-factor. The approximate Q-values are very close to the exact ones. The reduction in the Q-factor of the two variants of the proposed resonator due to losses when it is realized on the basis of an inverted microstrip line is 2.5 and 5.5%.
2
Xie, Yong Chao, Jin Yan Shi, and Xue Yong Ding. "Comparatively Study of Coaxial Waveguide and Open Coaxial Cavity." Advanced Materials Research 694-697 (May 2013): 1417–20. http://dx.doi.org/10.4028/www.scientific.net/amr.694-697.1417.
Full textAbstract:
In this paper, the computational formula of field distribution in a coaxial waveguide and the field distribution, resonant frequency and Q factors of open coaxial resonator are introduced. The S21 and the field profile of the TEM mode in a coaxial waveguide, and the field profile and E-field of the mode in a coaxial resonator is gained by the software CST microware studio. The truth that an open coaxial cavity is virtually a slow-varied section coaxial waveguide is gained.
3
Lv, Bing, Wentao Zhang, Wenzhu Huang, Fang Li, and Yongqian Li. "Narrow Linewidth Half-Open-Cavity Random Laser Assisted by a Three-Grating Ring Resonator for Strain Detection." Sensors 22, no. 20 (2022): 7882. http://dx.doi.org/10.3390/s22207882.
Full textAbstract:
A stabilized narrow-linewidth random fiber laser for strain detection, based on a three-grating ring (TGR) resonator and half-open-cavity structure, is proposed and investigated experimentally. The half-open-cavity structure proved to provide double optical gain of erbium-doped fiber, which was beneficial to increase the photon lifetime as well as further narrow the linewidth. Meanwhile, the stability and frequency noise of narrow lasing output was improved by suppressing the competition-induced undesired residual random lasing modes with the TGR resonator. The TGR resonator is composed of a double-cavity fiber Bragg grating Fabry–Perot (FBG-FP) interferometer, a section of single-mode fiber, and a circulator. The specially designed double-cavity FBG-FP interferometer embedded in the TGR resonator acted as the strain-sensing element and improved the resolution of the dynamic strain. A stable ultra-narrow linewidth of about 205 Hz was obtained. The frequency noise was reduced to about 2 Hz/√Hz. A high dynamic strain measuring resolution of 35 femto-strain (fε)/√Hz was achieved.
4
Lee, Yun-Min, Jin-Kook Kim, and Jung Hur. "Design of An Open-Ended Coaxial Cavity Resonator." Journal of the Institute of Webcasting, Internet and Telecommunication 13, no. 4 (2013): 201–8. http://dx.doi.org/10.7236/jiibc.2013.13.4.201.
Full text
5
Trubin, A. A. "Mutual Coupling Coefficients of Rotated Rectangular Dielectric Resonators in Open Space." Visnyk NTUU KPI Seriia - Radiotekhnika Radioaparatobuduvannia, no. 88 (June 30, 2022): 60–68. https://doi.org/10.20535/radap.2022.88.60-68.
Full textAbstract:
The coefficients of mutual coupling of rectangular dielectric resonators in open space are calculated under the condition of their rotation relative to one of the axes of a given rectangular coordinate system. Analytical formulas for complex coupling coefficients are obtained. The expressions found give complete information about the frequencies and Q-factor of coupled oscillations of dielectric resonators. The dependences of the coupling coefficients on the angles of rotation and spatial coordinates of resonators in the case of excitation of the main magnetic types of natural oscillations in them are considered. The concept of pseudo-rotation of resonators is introduced. Cases are noted when the pseudo-rotation of the resonators does not lead to a change in the coupling coefficients. The dependences of the coupling coefficients for different types of resonator pseudo-rotations are investigated. New integral representations are derived for the mutual coupling coefficients of rectangular dielectric resonators provided that their axes rotate in open space. In particular cases of parallelism of the resonator axes of one of the coordinate axes, the analytical expressions found in the work coincide with those obtained earlier. For each case of rotation, approximate analytical formulas are found for the integral representations obtained in this work, expressed in terms of the spherical Hankel functions of the second kind. Comparison of calculations of coupling coefficients by integral formulas and approximate expressions is carried out. It is shown that the approximate expressions have acceptable accuracy for all the considered cases of rotations. The dependences of the coupling coefficients on the coordinates of the resonators are investigated. The regions are marked in which the found integral representations make it possible to correctly describe the coupling coefficients of rectangular resonators. In contrast to integral representations, approximate formulas are correct in the entire spatial region of resonator interaction. The results obtained make it possible to construct analytical models of antennas, multi-element arrays and devices of infrared and optical wavelength ranges, made with the use of rectangular dielectric resonators; significantly reduce computation timecompared to numerical methods and optimize complex multi-cavity structures of microwave and optical communication systems.
6
Feng, Guo-Hua, and Wen-Sheng Chen. "Piezoelectric Micromachined Ultrasonic Transducer-Integrated Helmholtz Resonator with Microliter-Sized Volume-Tunable Cavity." Sensors 22, no. 19 (2022): 7471. http://dx.doi.org/10.3390/s22197471.
Full textAbstract:
In this study, a piezoelectric micromachined ultrasonic transducer (PMUT) is integrated with a microliter-sized volume-tunable Helmholtz resonator. The passive Helmholtz resonator is constructed using an SU8 photolithography-defined square opening plate as the neck portion, a 3D-printed hollow structure with a threaded insert nut, and a precision set screw to form the volume-controllable cavity of the Helmholtz resonator. The fabricated piezoelectric films acted as ultrasonic actuators attached to the surface of the neck SU8 plate. Experimental results show that the sound pressure level (SPL) and operation bandwidth could be effectively tuned, and a 200% SPL increase and twofold bandwidth enhancement are achieved when setting the cavity length to 0.75 mm compared with the open-cavity case. A modified Helmholtz resonator model is proposed to explain the experimental results. The adjusting factors of the effective mass and viscous damper are created to modify the existing parameters in the conventional Helmholtz resonator model. The relationship between the adjusting factors and cavity length can be described well using a two-term power series curve. This modified Helmholtz resonator model not only provides insight into this active-type Helmholtz resonator operation but also provides a useful estimation for its optimal design and fabrication.
7
Kottapalli, Shravan, Remco van de Meerendonk, Nicholas Waterson, Gunes Nakiboglu, Avraham Hirschberg, and David M. J. Smeulders. "Analytical modelling and experimental validation of compliance-based low-frequency resonators for water circuits." Acta Acustica 6 (2022): 56. http://dx.doi.org/10.1051/aacus/2022050.
Full textAbstract:
Transmission losses of compact compliance-based resonators in water circuits are investigated. Experiments are performed to measure the anechoic transmission losses (TLan) of flexible-plate resonators and a gas resonator designed for frequencies between 10 and 100 Hz. The measurements are compared to theoretical results based on a lumped-element model and a finite-element model. The TLan is measured using a robust form of the multi-microphone method, which gave identical results for open and closed pipe acoustic terminations at the transmission side of the setup. When an estimate of the reflection coefficient at the termination is known, good results are obtained with only one transmission-side microphone. When TLan is high, a single microphone is sufficient on each side. For the flexible-plate resonators the TLan measurements are in agreement with theory except close to resonance, where the transmission signals are below the detection limit. Due to assumptions of a rigid cavity wall and a clamped top-plate, the theoretical resonance frequencies are too high except for the thinnest plate which displays static deformation stiffening. This deformation stiffening limits the possibility to lower the resonance frequency by using a thin flexible plate in a circuit with high static pressure. Low resonance frequencies are easier to reach with a gas resonator, in which a piston separates the water from a volume filled with air. For the gas-resonator, the measurements agree with the theoretical predictions when assuming a significant damping. The friction between the air-water-separation piston and cavity wall is suspected to cause this damping. Theory predicts that the TLan of both resonators designed for same resonance frequencies in absence of losses are equivalent. They therefore have quite similar performances except close to the resonance frequency. The flexible-plate resonator has a higher quality factor and higher (TLan) around the resonance frequency. The gas resonator is more complex and needs more maintenance but allows fine tuning of the resonance frequency by varying the gas volume.
8
Wang, Jianguo, Philip Rubini, Qin Qin, and Brian Houston. "A Model to Predict Acoustic Resonant Frequencies of Distributed Helmholtz Resonators on Gas Turbine Engines." Applied Sciences 9, no. 7 (2019): 1419. http://dx.doi.org/10.3390/app9071419.
Full textAbstract:
Helmholtz resonators, traditionally designed as a narrow neck backed by a cavity, are widely applied to attenuate combustion instabilities in gas turbine engines. The use of multiple small holes with an equivalent open area to that of a single neck has been found to be able to significantly improve the noise damping bandwidth. This type of resonator is often referred to as “distributed Helmholtz resonator”. When multiple holes are employed, interactions between acoustic radiations from neighboring holes changes the resonance frequency of the resonator. In this work, the resonance frequencies from a series of distributed Helmholtz resonators were obtained via a series of highly resolved computational fluid dynamics simulations. A regression analysis of the resulting response surface was undertaken and validated by comparison with experimental results for a series of eighteen absorbers with geometries typically employed in gas turbine combustors. The resulting model demonstrates that the acoustic end correction length for perforations is closely related to the effective porosity of the perforated plate and will be obviously enhanced by acoustic radiation effect from the perforation area as a whole. This model is easily applicable for engineers in the design of practical distributed Helmholtz resonators.
9
Hedayati, Reza, and Sandhya P. Lakshmanan. "Active Acoustic Metamaterial Based on Helmholtz Resonators to Absorb Broadband Low-Frequency Noise." Materials 17, no. 4 (2024): 962. http://dx.doi.org/10.3390/ma17040962.
Full textAbstract:
The aim of the present work is to design active acoustic metamaterial consisting of an array of Helmholtz resonators and fabricating them using an additive manufacturing technique in order to assist in a reduction in noise levels in aerospace applications. To this aim, initially, a passive metamaterial consisting of an array of 64 Helmholtz resonator unit cells is designed and tested to establish the effectiveness and region of performance. The selected design variable for change is identified as the resonator cavity depth through the frequency response for each parameter of the Helmholtz resonance equation and randomized to achieve a broadband frequency range of the passive metamaterial. An active model of this design (actuated by a stepper motor) is fabricated and tested. The metamaterials are tested under two acoustic set-ups: a closed system aimed at recreating the environment of a soundproof room and an open-system aimed to recreate the condition of an active liner. For the case of passive system, the metamaterial gave sound attenuation of 18 dB (for f = 150 Hz) in open system configuration and 33 dB (f = 350 Hz) in closed system configuration. The attenuation obtained for the active model was 10–15 dB over the mean line performance for the case of closed system and 15–20 dB for the case of open system. The closed system was also tested for performance at multiple cavity depths by setting two wall depths at 10 mm and three walls at 50 mm. This test yielded an attenuation of 15 dB at 180 Hz, the frequency corresponding to 50 mm cavity depth, and 10 dB at 515 Hz, corresponding to 10 mm cavity depth.
10
Zhang, Liwei, Yewen Zhang, Xiaodong Chen, Xiaoming Liu, Li Zhang, and Hong Chen. "Energy transport in a metamaterial subwavelength open-cavity resonator." Optics Letters 36, no. 12 (2011): 2224. http://dx.doi.org/10.1364/ol.36.002224.
Full text
11
Stephan, K. D., and S. L. Young. "Open-cavity resonator as high-Q microstrip circuit element." Electronics Letters 23, no. 19 (1987): 1028. http://dx.doi.org/10.1049/el:19870720.
Full text
12
Nguyen, Van Son, Hoang Anh Dang, Van Dung Tran, et al. "Design of a tunable center frequency and small size cavity bandpass filter by separating capacitor-loaded resonators." Indonesian Journal of Electrical Engineering and Computer Science 35, no. 3 (2024): 1456. http://dx.doi.org/10.11591/ijeecs.v35.i3.pp1456-1467.
Full textAbstract:
This paper presents a tunable center frequency and small size cavity bandpass filter design method. In this method, a capacitor-loaded open terminal coaxial resonator is employed to reduce the size of cavity filters. The resonator is designed and fabricated separately into two parts to achieve the flexible operating frequency purpose. The first part is called the base of the resonator which is simply a pillar and directly fabricated integrally with the cavity housing. The second part called the hat of the resonator is the main part causing the load capacitance in cavity filters. By using different heights of the base part or/and different shapes and sizes of the hat, the operating frequency of cavity filters can be changed flexibly. This method not only reduces the difficulty and cost of cavity filter processing but also makes cavity filters reconfigurable. To demonstrate the effectiveness of the method, a cavity filter sample with a center frequency of 3.45 GHz and a bandwidth of 80 MHz was designed, fabricated, and measured. The measured results show that the insertion loss was smaller than 1.33 dB in the whole bandwidth, one zero-point at 3.350 GHz reaching -68 dB, the rejection at 3.550 GHz was -41 dB, unloaded Q was 5,898, and the dimension of the filter was 128 mm×86 mm×23 mm.
13
Van, Son Nguyen Hoang Anh Dang Van Dung Tran Cao Dai Pham Thi Bich Phan Van Trung Nguyen Xuan Loi Dai Long Tran Huy. "Design of a tunable center frequency and small size cavity bandpass filter by separating capacitor-loaded resonators." Indonesian Journal of Electrical Engineering and Computer Science 35, no. 3 (2024): 1456–67. https://doi.org/10.11591/ijeecs.v35.i3.pp1456-1467.
Full textAbstract:
This paper presents a tunable center frequency and small size cavity bandpass filter design method. In this method, a capacitor-loaded open terminal coaxial resonator is employed to reduce the size of cavity filters. The resonator is designed and fabricated separately into two parts to achieve the flexible operating frequency purpose. The first part is called the base of the resonator which is simply a pillar and directly fabricated integrally with the cavity housing. The second part called the hat of the resonator is the main part causing the load capacitance in cavity filters. By using different heights of the base part or/and different shapes and sizes of the hat, the operating frequency of cavity filters can be changed flexibly. This method not only reduces the difficulty and cost of cavity filter processing but also makes cavity filters reconfigurable. To demonstrate the effectiveness of the method, a cavity filter sample with a center frequency of 3.45 GHz and a bandwidth of 80 MHz was designed, fabricated, and measured. The measured results show that the insertion loss was smaller than 1.33 dB in the whole bandwidth, one zero-point at 3.350 GHz reaching -68 dB, the rejection at 3.550 GHz was -41 dB, unloaded Q was 5,898, and the dimension of the filter was 128 mm×86 mm×23 mm.
14
Di Massa, G., S. Costanzo, and O. H. Moreno. "Open Resonator System for Reflectarray Elements Characterization." International Journal of Antennas and Propagation 2012 (2012): 1–7. http://dx.doi.org/10.1155/2012/912809.
Full textAbstract:
An open resonator system is proposed in this work to study the phase behavior of reflectarrays cells. The characterization of the single reflectarray element is performed by assuming a Gaussian plane wave normally incident on an infinite periodic array of identical radiating elements. An equivalent circuit model is properly derived for the open cavity including the reflectarray test structure, in order to retrieve the phase design curve of the single reflectarray element. K-band experimental validations are presented and discussed to show the effectiveness of the approach.
15
Paul, Robert B., A. Ege Engin, and Jerry Aguirre. "Flip Chip Underfill RF Characterization." International Symposium on Microelectronics 2019, no. 1 (2019): 000243–47. http://dx.doi.org/10.4071/2380-4505-2019.1.000243.
Full textAbstract:
Abstract To develop reliable high-speed packages, characterization of the underfill material used in the flip-chip process has become of greater importance. The underfill, typically an epoxy resin-based material, offers thermal and structural benefits for the integrated circuit (IC) on package. With so many inputs and outputs (IOs) in close proximity to one another, the integrated circuits on package can have unexpected signal and power integrity issues. Furthermore, chip packages can support signals only up to the frequency where noise coupling (e.g., crosstalk, switching noise, etc.) leads to the malfunctioning of the system. Vertical interconnects, such as vias and solder bumps, are major sources of noise coupling. Inserting ground references between every signal net is not practical. For the solder bumps, the noise coupling depends on the permittivity of the underfill material. Therefore, characterizing the permittivity of the underfill material helps in predicting signal and power integrity issues. Such liquid or semi-viscous materials are commonly characterized from a simple fringe capacitance model of an open-ended coaxial probe immersed in the material. The open-ended coaxial method, however, is not as accurate as resonator-based methods. There is a need for a methodology to accurately extract the permittivity of liquid or semi-viscous materials at high frequencies. The proposed method uses solid walled cavity resonators, where the resonator is filled with the underfill material and cured. Dielectric characterization is a complex process, where the physical characteristics of the cavities must be known or accurately measured. This includes the conductivity of the conductors, roughness of the conductors, the dimensions of the cavity, and the port pin locations. This paper discusses some of the challenges that are encountered when characterizing dielectrics with cavity resonators. This characterization methodology can also be used to characterize other materials of interest.
16
Müller, Jens. "Wide Band Measurement of Dielectric Properties of Electronic Assembly Materials Inside an LTCC Fluidic Structure." Journal of Microelectronics and Electronic Packaging 11, no. 2 (2014): 64–69. http://dx.doi.org/10.4071/imaps.400.
Full textAbstract:
Assembly materials such as underfillers or glob top epoxies are typically not specified regarding their dielectric properties for frequencies higher than 1 MHz. However, their behavior should be known for a wider frequency range in order to implement the appropriate parameters for RF and microwave simulations and designs. Typical methods to measure permittivity and loss tangent are based on parallel plate capacitor measurement with an impedance or network analyzer (up to about 1 GHz), S-parameter measurement of filled waveguides, coaxial transmission lines, or resonance methods (e.g., split post resonator, slit cavity resonator, ring resonator, open resonator). Most of these methods require specific sophisticated sample preparation. The paper describes a novel method based on suspended or inverted microstrip evaluation in a 3D LTCC structure. Suspended and inverted microstrip lines have lower insertion losses than standard microstrip lines due to the air gap between the line and the ground plane (reduced dielectric losses). Low loss structures are necessary to be able to measure low loss dielectrics. Such suspended or inverted microstrip lines can be easily achieved in LTCC by implementing a cavity structure. Inlets and outlets allow for the cavity to be filled with fluids after an initial S-parameter measurement of line properties (i.e., impedance, insertion loss, phase velocity). Measuring is repeated once the assembly material is cured. The change in impedance, phase velocity, and insertion contains the information about the material under test. Its properties are derived by curve fitting methods with a 3D electromagnetic field simulator. It is also possible to implement line resonators instead of through lines. In the latter case, the resonant frequency shift and the quality factor contains the material information. The procedure is demonstrated on a multilayer LTCC substrate based on low loss DP 9k7 and a commercial underfill material.
17
Müller, Jens. "Wide Band Measurement of Dielectric Properties of Electronic Assembly Materials Inside a LTCC Fluidic Structure." Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT) 2013, CICMT (2013): 000041–46. http://dx.doi.org/10.4071/cicmt-tp22.
Full textAbstract:
Assembly materials like underfillers or glob top epoxies are typically not specified regarding their dielectric properties for frequencies higher than 1 MHz. However, their behavior should be known for a wider frequency range in order to implement the right parameters for RF and microwave simulations and designs. Typical methods to measure permittivity and loss tangent are based on parallel plate capacitor measurement with an impedance or network analyzer (up to about 1 GHz), S-parameter measurement of filled wave guides or coaxial transmission lines or resonance methods (e.g. split post resonator, slit cavity resonator, ring resonator, open resonator). Most of these methods require specific sophisticated sample preparation. The paper describes a novel method based on suspended or inverted microstrip evaluation in a 3D LTCC structure. Suspended and inverted microstrip lines have lower insertion losses than standard microstrip lines due to the air gap between the line and the ground plane (reduced dielectric losses). Low loss structures are necessary to be able to measure low loss dielectrics. Such suspended or inverted microstrip lines can be easily achieved in LTCC by implementing a cavity structure. In- and outlets allow filling the cavity with fluids after an initial S-parameter measurement of line properties (impedance, insertion loss, phase velocity). Measuring is repeated once the assembly material is cured. The change in impedance, phase velocity and insertion contains the information about the material under test. Its properties are derived by curve fitting methods with a 3D electromagnetic field simulator. It is also possible to implement line resonators instead of through lines. In the latter case, the resonant frequency shift and the quality factor contains the material information. The procedure is demonstrated on a multilayer LTCC substrate based on low loss DP 9k7 and a commercial underfill material.
18
Mongia, R. K., and R. K. Arora. "Equivalent circuit parameters of an aperture coupled open resonator cavity." IEEE Transactions on Microwave Theory and Techniques 41, no. 8 (1993): 1245–50. http://dx.doi.org/10.1109/22.241661.
Full text
19
Stephan, K. D., and S. L. Young. "Erratum: Open-cavity resonator as high-Q microstrip circuit element." Electronics Letters 23, no. 25 (1987): 1397. http://dx.doi.org/10.1049/el:19870966.
Full text
20
Zhang, Zhuo-Zhi, Xiang-Xiang Song, Gang Luo, et al. "Coherent phonon dynamics in spatially separated graphene mechanical resonators." Proceedings of the National Academy of Sciences 117, no. 11 (2020): 5582–87. http://dx.doi.org/10.1073/pnas.1916978117.
Full textAbstract:
Vibrational modes in mechanical resonators provide a promising candidate to interface and manipulate classical and quantum information. The observation of coherent dynamics between distant mechanical resonators can be a key step toward scalable phonon-based applications. Here we report tunable coherent phonon dynamics with an architecture comprising three graphene mechanical resonators coupled in series, where all resonators can be manipulated by electrical signals on control gates. We demonstrate coherent Rabi oscillations between spatially separated resonators indirectly coupled via an intermediate resonator serving as a phonon cavity. The Rabi frequency fits well with the microwave burst power on the control gate. We also observe Ramsey interference, where the oscillation frequency corresponds to the indirect coupling strength between these resonators. Such coherent processes indicate that information encoded in vibrational modes can be transferred and stored between spatially separated resonators, which can open the venue of on-demand phonon-based information processing.
21
Tian, Kun Peng, Gao Feng Guo, Jun Hu Wang, and En Li. "Measurement of Complex Permittivity of Insulating Substrates with an Open-Ended Coaxial Resonator." Advanced Materials Research 1052 (October 2014): 427–32. http://dx.doi.org/10.4028/www.scientific.net/amr.1052.427.
Full textAbstract:
A novel cavity perturbation technique utilizing open-ended coaxial resonator is presented in order to measure the complex permittivity of insulating substrates at microwave frequencies. This technique can afford quite high accurate measurement results without singularities, and simply. According to the operation frequency of the resonator, the geometric parameters of the resonator are designed. Based on the perturbation technique, a new formulaic method of data analysis has been proposed which can extract complex permittivity of samples, and with the resonant frequency and the quality factor shift, one can calculate the complex permittivity of the measured materials. Experiment has been conducted with the quartz and sapphire to verify the formulaic, and the test results fully verify the correctness of the proposed method.
22
Gonzalez-Ballestero, C. "Tutorial: projector approach to master equations for open quantum systems." Quantum 8 (August 29, 2024): 1454. http://dx.doi.org/10.22331/q-2024-08-29-1454.
Full textAbstract:
Most quantum theorists are familiar with different ways of describing the effective quantum dynamics of a system coupled to external degrees of freedom, such as the Born-Markov master equation or the adiabatic elimination. Understanding the deep connection between these -- sometimes apparently unrelated -- methods can be a powerful tool, allowing us to derive effective dynamics in unconventional systems or regimes. This tutorial aims at providing quantum theorists across multiple fields (e.g., quantum and atom optics, optomechanics, or hybrid quantum systems) with a self-contained practical toolbox to derive effective quantum dynamics, applicable to systems ranging from N-level emitters to mechanical resonators. First, we summarize the projector approach to open quantum systems and the derivation of the fundamental Nakajima-Zwanzig equation. Then, we show how three common effective equations, namely the Brownian master equation, the Born-Markov master equation, and the adiabatic elimination used in atom and molecular optics, can be derived from different perturbative expansions of the Nakajima-Zwanzig equation. We also solve in detail four specific examples using this formalism, namely a harmonic oscillator subject to displacement noise, the effective equations of a mechanical resonator cooled by an optical cavity, the Purcell effect for a qubit coupled to an optical cavity, and the adiabatic elimination in a Lambda system.
23
Lee, Yun-Min, Jin-Kook Kim, and Jung Hur. "Study on the empirical design of open-ended coaxial cavity resonator." Microwave and Optical Technology Letters 56, no. 3 (2014): 606–10. http://dx.doi.org/10.1002/mop.28150.
Full text
24
Fedotov, Alexey, Ilya Kurakin, Sebastian Fischer, Thomas Vogl, Thomas F. Prisner, and Vasyl Denysenkov. "Increased flow rate of hyperpolarized aqueous solution for dynamic nuclear polarization-enhanced magnetic resonance imaging achieved by an open Fabry–Pérot type microwave resonator." Magnetic Resonance 1, no. 2 (2020): 275–84. http://dx.doi.org/10.5194/mr-1-275-2020.
Full textAbstract:
Abstract. A continuous flow dynamic nuclear polarization (DNP) employing the Overhauser effect at ambient temperatures can be used among other methods to increase sensitivity of magnetic resonance imaging (MRI). The hyperpolarized state of water protons can be achieved by flowing aqueous liquid through a microwave resonator placed directly in the bore of a 1.5 T MRI magnet. Here we describe a new open Fabry–Pérot resonator as DNP polarizer, which exhibits a larger microwave exposure volume for the flowing liquid in comparison with a cylindrical TE013 microwave cavity. The Fabry–Pérot resonator geometry was designed using quasi-optical theory and simulated by CST software. Performance of the new polarizer was tested by MRI DNP experiments on a TEMPOL aqueous solution using a blood-vessel phantom. The Fabry–Pérot resonator revealed a 2-fold larger DNP enhancement with a 4-fold increased flow rate compared to the cylindrical microwave resonator. This increased yield of hyperpolarized liquid allows MRI applications on larger target objects.
25
Iqbal, Amjad, Jun Jiat Tiang, Sew Kin Wong, Mohammad Alibakhshikenari, Francisco Falcone, and Ernesto Limiti. "Multimode HMSIW-Based Bandpass Filter with Improved Selectivity for Fifth-Generation (5G) RF Front-Ends." Sensors 20, no. 24 (2020): 7320. http://dx.doi.org/10.3390/s20247320.
Full textAbstract:
This article presents the detailed theoretical, simulation, and experimental analysis of a half-mode substrate integrated waveguide (HMSIW)-based multimode wideband filter. A third-order, semicircular HMSIW filter is developed in this paper. A semicircular HMSIW cavity resonator is adopted to achieve wide band characteristics. A U-shaped slot (acts as a λ/4 stub) in the center of a semicircular HMSIW cavity resonator and L-shaped open-circuited stubs are used to improve the out-of-band response by generating multiple transmission zeros (TZs) in the stop-band region of the filter. The TZs on either side of the passband can be controlled by adjusting dimensions of a U-shaped slot and L-shaped open-circuited stubs. The proposed filter covers a wide fractional bandwidth, has a lower insertion loss value, and has multiple TZs (which improves the selectivity). The simulated response of filter agrees well with the measured data. The proposed HMSIW bandpass filter can be integrated with any planar wideband communication system circuit, thanks to its planar structure.
26
Njane, Stephen N., Yoshiaki Shinohara, Naoshi Kondo, Yuichi Ogawa, Tetsuhito Suzuki, and Takahisa Nishizu. "Improved underwater Helmholtz resonator with an open cavity for sample volume estimation." Computers and Electronics in Agriculture 147 (April 2018): 18–26. http://dx.doi.org/10.1016/j.compag.2018.02.015.
Full text
27
Bennet-Clark, H., and D. Young. "THE SCALING OF SONG FREQUENCY IN CICADAS." Journal of Experimental Biology 191, no. 1 (1994): 291–94. http://dx.doi.org/10.1242/jeb.191.1.291.
Full textAbstract:
In male cicadas, sound is generated by a pair of tymbals on the abdomen (Pringle, 1954). The tymbals buckle inwards causing pressure changes in the abdominal cavity, from which sound is radiated through the tympana (Young, 1990). A recent model of sound production in cicadas suggests that the abdominal cavity and tympana act as the components of a Helmholtz resonator that is excited by the drive from the tymbals (Bennet-Clark and Young, 1992). A Helmholtz resonator consists of a cavity open to the outside via a hole which has a real or notional neck, and the resonant frequency fo is given by the general equation: where c is the speed of sound in the fluid, taken as 340 m s-1 for air, A is the area of the neck, L is the length of the neck and V is the volume of the cavity. Where the resonator has two holes, these terms should be somewhat modified: A is the combined area of the two holes, L is 16/3pi r (~1.7r) for a simple hole in a thin-walled vessel and r is the radius of one hole (Seto, 1971). These modifications to equation 1, which include corrections for the acoustic end-effect at either side of a simple hole in the wall of a vessel, are applicable to a model of the male cicada, in which there are two tympana close to the ventral surface of the abdomen.
28
Razhev, A. M., D. S. Churkin та R. A. Tkachenko. "Neon lasing (λ = 540.1 nm) in a dense optical cavity pumped by a pulsed inductive cylindrical discharge". Laser Physics 33, № 2 (2023): 025003. http://dx.doi.org/10.1088/1555-6611/acaea0.
Full textAbstract:
Abstract The experimental results of the lasing characteristics dependence of the inductive neon laser (λ = 540.1 nm) on the optical cavity quality factor are presented. In the described experiments, the laser was operated in the amplified spontaneous emission mode. A frontal-substrate resonator (made according to the type of an open Fabry–Perot interferometer) was used, as well as a dense resonator with a reflection coefficient of the front mirror of 82%. Replacing the front substrate with an output mirror resulted in an increase in the lasing energy and optical pulse duration from 8.5 μJ to 41 μJ and from 10.0 ± 0.1 ns to 14.8 ± 0.1 ns, respectively. It is shown that the use of a dense resonator allows us to change the shape of the laser beam in the far field from annular to circular and to obtain intensity distribution close to uniform.
29
Syafrin, Rani Rahmawati, Cahyo Mustiko O. M, and Sudi M. Al Sasongko. "DETEKSI KEASLIAN MADU TRIGONA BERDASARKAN NILAI DIELEKTRIK DAN KONDUKTIVITAS MENGGUNAKAN TEKNIK OPEN - ENDED COAXIAL CAVITY RESONATOR PADA FREKUENSI 100 – 1000 MHz." DIELEKTRIKA 5, no. 1 (2018): 16–20. http://dx.doi.org/10.29303/dielektrika.v5i1.122.
Full textAbstract:
Teknik Open – Ended Coaxial Cavity Resonator merupakan sebuah teknik pengukuran schatering parameter dengan memanfaatkan gelombang mikro. Penelitian ini menggunakan teknik refleksi gelombang mikro melalui perantara Open – Ended Coaxial Cavity Resonator satu port yang terhubung dengan VNWA sebagai alat ukur pada sampel Madu Trigona. Pengukuran dilakukan pada rentang frekuensi 100 – 1000 MHz. Masing – masing sampel Madu Trigona memiliki kadar campuran larutan gula yang berbeda yaitu mulai dari 0% hingga 25% pada interval 5%. Pada proses perhitungan nilai dielektrik kompleks dan konduktivitas menggunakan teknik kalibrasi larutan garam yang memerlukan nilai koefisien refleksi (S11) terukur. Pengaruh penambahan larutan gula menyebabkan nilai dielektrik kompleks dan konduktivitas pada frekuensi tertentu semakin meningkat seperti pada frekuensi 502,5 MHz didapatkan nilai dielektrik kompleks campuran dari 15,355 – j18,435 hingga 21,749 – j24,560 sedangkan nilai konduktivitas dari 0,5153 hingga 0,6866 S/m. Sedangkan pengaruh frekuensi menyebabkan perubahan nilai dielektrik kompleks yang semakin menurun dan konduktivitas akan semakin meningkat, seperti pada sampel madu Trigona dengan larutan gula 10% didapatkan nilai dielektrik kompleks dari 38,488 – j55,613 hingga 11,346 – j10,035 dan nilai konduktivitas dari 0,3094 hingga 0,5583 S/m.
 Kata kunci: VNWA, Madu Trigona, dielektrik kompleks, konduktivitas.
30
Wu, Fan, and Kwai Man Luk. "Wideband High-Gain Open Resonator Antenna Using a Spherically Modified, Second-Order Cavity." IEEE Transactions on Antennas and Propagation 65, no. 4 (2017): 2112–16. http://dx.doi.org/10.1109/tap.2016.2647700.
Full text
31
Kundu, Chitresh, Prabal Patra, Bipan Tudu, and Dibyayan Patra. "Measurement of Temperature Dependent Dielectric Constant of Coal Samples for Burden Surface Profiling at Blast Furnace." Journal of Experimental Techniques and Instrumentation 4, no. 2 (2021): 38–51. http://dx.doi.org/10.30609/jeti.v4i2.12584.
Full textAbstract:
Blast furnaces (BFs) are the key receptacles of iron and steel smelting. Iron ore, coke and limestone are some of the raw materials that are used in the process of iron making and the charging operation needs to be accomplished by accurately estimating the current depth of the burden surface. To accomplish the goal of global class steel production, burden profile measurement and monitoring is vital. This measuring and monitoring help in augmenting the best usage of charge materials and energy consumptions.
 Radar based measurement is best for determine the level and profile of the burden inside the furnace. However, for the optimal operation of the radar, it is important know the dielectric constant of the material. There are many approaches to determine the dielectric constant like capacitive methods, transmission line methods, cavity resonator methods, open cavity methods and so on. For this study the cavity resonator method is has been used for measuring the permittivity of coal samples. The reflection capability of electromagnetic waves by coal is a function of its dielectric properties which is also has a dependency on temperature. The results presented in this paper will provide essential design input for radar-based measurements at blast furnace, especially for burden profiling at blast furnaces.
32
Kou, Ke, Tianhong Lian, Cuo Wang, and Guanlei Zhang. "Developing open cavity solid-state laser for self-mixing sensor." Sensor Review 39, no. 2 (2019): 252–56. http://dx.doi.org/10.1108/sr-12-2017-0263.
Full textAbstract:
PurposeAs an emerging measurement technique with the merit of easy alignment and high sensitivity, laser self-mixing interferometry (SMI) has wide applications in the detection of physical quantities. Considering that the characteristics of lasers have a determining influence on sensors’ performance, the authors have established an open cavity solid-state laser (SSL) with more adjustment flexibility to act as a laser source.Design/methodology/approachThe fundamental structure of a SSL has been presented with an Nd:YAG rod severing as an active material and a birefringent filter inserted in the resonator as a mode selecting element. The power stability has been tested by a power meter, while the mode pattern has been inspected with a scanning Fabry–Perot interferometer, and the linewidth has been observed through a wavelength meter. A loudspeaker driven by a function generator is located in the extracavity to introduce phase modulation for SMI signal observation.FindingsThe established Nd:YAG SSL operates in a single longitudinal mode with the power stability of 0.2 mW and the linewidth less than 10 MHz. The SMI phenomenon occurs in the SSL, and the SMI signal obtained shows a fine signal-to-noise ratio of about 30 dB.Originality/valueTo the authors knowledge, SMI sensors using SSLs, especially in open cavity type, have rarely been reported, and they can find significant applications in designing high performance SMI sensors and instruments.
33
Olmi, Roberto, Saverio Priori, Alberto Toccafondi, and Federico Puggelli. "An Open-Resonator Sensor for Measuring the Dielectric Properties of Antarctic Ice." Sensors 19, no. 9 (2019): 2099. http://dx.doi.org/10.3390/s19092099.
Full textAbstract:
In this paper, the theory behind the design of a microwave sensor for the accurate measurement of firn complex permittivity is presented. This class of microwave sensors, based on the open-coaxial re-entrant cavity method, is specifically designed to measure, by means of a simple and quick procedure, the complex permittivity profile of low loss materials. A calibration procedure is introduced to derive the complex permittivity of the material under measurement (MUM). Two specimens of this class of microwave sensors have been realized to sample the complex permittivity profile of a 106-m long ice core drilled from the Antarctic plateau at Concordia Station. The preliminary results of the on site measurement campaign are reported, showing very good agreement with theoretical models available in the literature.
34
Lee, Yun-Min, Jin-Kuk Kim, and Jung Hur. "A Study on the Detection of the Rain Using Open-Ended Coaxial Cavity Resonator." Journal of Korean Institute of Electromagnetic Engineering and Science 24, no. 9 (2013): 944–50. http://dx.doi.org/10.5515/kjkiees.2013.24.9.944.
Full text
35
Mira, Fermín, Jordi Mateu, and Carlos Collado. "Mechanical Tuning of Substrate Integrated Waveguide Filters." IEEE Transactios on Microwave Theory and Techniques 63, no. 12 (2015): 3939–46. https://doi.org/10.5281/zenodo.46154.
Full textAbstract:
This paper presents a novel approach for tuning substrate integrated waveguide resonators, realized by placing an additional metallized via-hole on the waveguide cavity. The approach presented here can be applied as a trimming technique, as well as to develop filter designs with tunable center frequencies and tunable bandwidths. Three different filters are designed and implemented, demonstrating excellent trimming, 10% tuning of the center frequency, and 100% tuning of the bandwidth, respectively.
36
Simon, Frank, Delphine Sebbane, and surname given-names. "Compact 2DOF liner based on a long elastic open-neck acoustic resonator for low frequency absorption." Noise Control Engineering Journal 69, no. 1 (2021): 1–17. http://dx.doi.org/10.3397/1/37691.
Full textAbstract:
Passive acoustic liners, used in aeronautic engine nacelles to reduce radiated fan noise, have a quarter-wavelength behavior. The simplest systems are SDOF-type (single degree of freedom), consisting of a perforated sheet backed with a honeycomb, whose absorption ability is limited to frequencies near the Helmholtz frequency. Thus, to widen the absorption frequency range, manufacturers use a 2DOF (double degree of freedom) system, with an internal layer over another honeycomb (stack of two resonators). However, one constraint is the limited thickness of the overall system, which reduces the space allotted to each honeycomb. A possible approach, based on a previous concept called LEONAR (long elastic open-neck acoustic resonator), could be to link each perforated layer to hollow tubes inserted in each honeycomb layer, in order to shift resonance frequencies to lower frequencies by extending the air column lengths. The presence of an empty chamber on both sides of the internal perforated layer also allows the tube length to be increased through tubes crossing both cavities, preserving the liner thickness. The main aim of this article is to mathematically describe the principle of a 2DOF LEONAR and to show the relevance of the mathematical model through FEM simulations and experiments performed in an impedance tube. Moreover, its behavior is analyzed through a parametric study, in order to explore its potential for an aeronautic application. A remarkable feature of 2DOF LEONAR-type materials with insertion of bottom tubes in the higher cavity is the possibility of maintaining the low frequency band provided by the original LEONAR concept, while adding a second absorption peak at a higher frequency, by the second layer and the accompanying tubes. There is a fundamental difference from classical SDOF/2DOF resonators, for which the thicknesses are obviously different.
37
Gynevski, Aron, and Polina Landa. "Exitation of hydrodynamic and acoustic waves in subsonic jet and separation flows." Izvestiya VUZ. Applied Nonlinear Dynamics 3, no. 2 (1995): 42–59. https://doi.org/10.18500/0869-6632-1995-3-2-42-59.
Full textAbstract:
Review of phenomena (aking place in subsonic jet and separation flows is given. Both free jets and jets interacting with different obstacles (for example, with a plane flat, cavity or acoustic resonator аs in open-jet return-circuit wind tunnels) are considered. Experimental data for flow along а stationary cylinder and а cylinder executing lateral periodic vibrations are set out. The presentation and trying to find the sense of all results are given from the point of view of the oscillation and wave theory.
38
Zhang, Baoguo, Mingrong Dong, Bin He, et al. "A high-intensity low-frequency acoustic generator based on the Helmholtz resonator and airflow modulator." PLOS ONE 19, no. 3 (2024): e0300832. http://dx.doi.org/10.1371/journal.pone.0300832.
Full textAbstract:
The high-intensity low-frequency acoustic sources have essential applications in acoustic biological effects research, airport bird repelling, and boiler ash removal. However, generating high-intensity low-frequency acoustic waves in open space is difficult. In this paper, a low-frequency acoustic generator with a resonant cavity used to enhance the acoustic intensity in open space was developed, which is an aerodynamic acoustic generator to radiates a high-intensity acoustic wave of 52Hz. Some experiments were carried out to measure this generator’s internal flow field and radiated acoustic field characteristics, including the propagation characteristics at 100m. The experimental results show that the resonant enhancement effect is presented near the predetermined resonance frequency, and the enhanced value is about 4dB. The acoustic intensity for 52Hz at 1m position is 124dB. By combining the Helmholtz resonator with the airflow modulator, the airflow resonance in the resonator enhances the air pressure pulsation inside the chamber and increases the disturbance of acoustic radiation to the air. So as to improve the sound intensity and radiation efficiency in the low-frequency range.
39
Tuhkala, M., J. Juuti, and H. Jantunen. "Determination of complex permittivity of surfactant treated powders using an open-ended coaxial cavity resonator." Powder Technology 256 (April 2014): 140–45. http://dx.doi.org/10.1016/j.powtec.2014.02.016.
Full text
40
Lee, Chih-Kuo, Jack McGhee, Christos Tsipogiannis, et al. "Evaluation of Microwave Characterization Methods for Additively Manufactured Materials." Designs 3, no. 4 (2019): 47. http://dx.doi.org/10.3390/designs3040047.
Full textAbstract:
Additive manufacturing (AM) has become more important and common in recent years. Advantages of AM include the ability to rapidly design and fabricate samples much faster than traditional manufacturing processes and to create complex internal geometries. Materials are crucial components of microwave systems and proper and accurate measurement of their dielectric properties is important to aid a high level of accuracy in design. There are numerous measurement techniques and finding the most appropriate method is important and requires consideration of all different factors and limitations. One limitation of sample preparation is that the sample size needs to fit in the measurement method. By utilizing the advantage of additive manufacturing, the material can be characterized using different measurement methods. In this paper, the additive manufacturing process and dielectric measurement methods have been critically reviewed. The test specimens for measuring dielectric properties were fabricated using fused filament fabrication (FFF)-based additive manufacturing and were measured using four different commercial dielectric properties measurement instruments including split post dielectric resonator (SPDR), rectangular waveguide, TE01δ cavity resonator, and open resonator. The measured results from the four techniques have been compared and have shown reasonable agreement with measurements within a 10 percent range.
41
Wang, Jingchao, Rui Wang, Lezhong Li, Junlin Guo, and Jian Zhang. "Design of a New Capacitive Load Cross-Coupled Cavity Filter." Electronics 12, no. 1 (2022): 142. http://dx.doi.org/10.3390/electronics12010142.
Full textAbstract:
This paper presents a new design method for a capacitor-loaded cross-coupled cavity filter, which significantly increases the power capacity of the cavity filter while improving out-of-band rejection. The filter uses a coaxial resonator at the open end of the donut capacitive-load. A triangular form of cavity structure is used for the full-cavity arrangement to reduce the size of the filter. In order to validate the design, a filter with a center frequency of 2.08 GHz and bandwidth of 80 MHz was designed, processed, and tested. The measured insertion loss was ≤0.97 dB, and the return loss was >20 dB in the range of 2040 MHz to 2120 MHz; the rejection was as high as 80 dB, and in-band ripple was 0.06 dB in the upper and lower stopband-range, which was only 30 MHz away from the sideband. After a simulation of the model using HFSS software (HFSS 2021, Canonsburg, PA, USA), the measured results matched the simulation results, which verified the correctness and practicality of the design. Compared with the ordinary-disc-load resonant cavity, the new donut capacitively loaded cavity-bandpass-filter has a 13.2% reduction in height and a 29.7% increase in power capacity.
42
Norhanani, Abd Rahman, Zakaria Zahriladha, Abd Rahim Rosemizi, Dasril Yosza, and Azuan Mohd Bahar Amyrul. "Planar Microwave Sensors for Accurate Measurement of Material Characterization: A Review." TELKOMNIKA Telecommunication, Computing, Electronics and Control 15, no. 3 (2017): 1108–18. https://doi.org/10.12928/TELKOMNIKA.6684.
Full textAbstract:
Microwave sensor is used in various industrial applications and requires highly accurate measurements for material properties. Conventionally, cavity waveguide perturbation, free-space transmission, open-ended coaxial probe, and planar transmission line technique have been used for characterizing materials. However, these planar transmission lines are often large and expensive to build, further restricting their use in many important applications. Thus, this technique is cost effective, easy to manufacture and due to its compact size, it has the potential to produce sensitivity and a high Q-factor for various materials. This paper reviews the common characteristics of planar transmission line and discusses numerous studies about several designs of the microstrip resonator to improve the sensor performance in terms of the sensitivity and accuracy. This technique enables its use for several industrial applications such as agriculture and quality control. It is believed that previous studies would lead to a promising solution of characterizing materials with high sensitivity, particularly in determining a high Qfactor resonator sensor.
43
Trubin, A. A. "Scattering of Electromagnetic Waveson Lattices of Rectangular Dielectric Resonators." Visnyk NTUU KPI Seriia - Radiotekhnika Radioaparatobuduvannia, no. 84 (March 30, 2021): 5–10. https://doi.org/10.20535/radap.2021.84.5-10.
Full textAbstract:
The c-functions that determine the degree of influence of an external exciting electromagnetic field on a rectangular dielectric resonator (DR) in open space are calculated and investigated. The presence of directions with ''zero'' projection of the exciting electromagnetic field onto the DR field is shown. Using the perturbation theory, the spatial distribution of the scattered electromagnetic fields, which arises when a plane electromagnetic wave of p-, or s-type, is incident on a square lattice of rectangular dielectric resonators is studied. An electromagnetic model of scattering on a rectangular DR lattice is constructed. The appearance of a reflected and shadow lobe during scattering by a lattice of rectangular DRs with basic magnetic modes is demonstrated. The features of scattering by a cubic lattice with degenerate magnetic oscillations of the main type are investigated. It is shown that the degeneracy of the eigenoscillations of the resonators leads to a more complex scattering pattern: the appearance of additional lobes, as well as a change in their shape. It is noted that the shape of the spatial distribution of the scattered electromagnetic field of the grating can change noticeably with frequency variation within the frequency band of coupled oscillations of the resonators of the lattice. The obtained practical simulation results make it possible to significantly reduce the computation time and optimize complex multi-cavity structures of microwave and optical communication systems that simultaneously perform the functions of separation or combining of channels.
44
Kira, Ahmed, Mohannad Y. Elsayed, Karim Allidina, Vamsy P. Chodavarapu та Mourad N. El-Gamal. "A 6.89-MHz 143-nW MEMS Oscillator Based on a 118-dBΩ Tunable Gain and Duty-Cycle CMOS TIA". Electronics 10, № 21 (2021): 2646. http://dx.doi.org/10.3390/electronics10212646.
Full textAbstract:
This article presents a 6.89 MHz MEMS oscillator based on an ultra-low-power, low-noise, tunable gain/duty-cycle transimpedance amplifier (TIA) and a bulk Lamé-mode MEMS resonator that has a quality factor (Q) of 3.24 × 106. Self-cascoding and current-starving techniques are used in the TIA design to minimize the power consumption and tune the duty-cycle of the output signal. The TIA was designed and fabricated in TSMC 65 nm CMOS process technology. Its open-loop performance has been measured separately. It achieves a tunable gain between 107.9 dBΩ and 118.1 dBΩ while dissipating only 143 nW from a 1 V supply. The duty-cycle of the output waveform can be tuned from 23.25% to 79.03%. The TIA has been interfaced and wire bonded in a series-resonant oscillator configuration with the MEMS resonator and mounted in a small cavity standard package. The closed-loop performance of the whole oscillator has been experimentally measured. It exhibits a phase noise of −128.1 dBc/Hz and −133.7 dBc/Hz at 1 kHz and 1 MHz offsets, respectively.
45
Zhang, Liwei, Yewen Zhang, Xiaodong Chen, Xiaoming Liu, Li Zhang, and Hong Chen. "Study on the Tunneling Mode in a Sub-Wavelength Open-Cavity Resonator Consisting of Single Negative Materials." IEEE Transactions on Antennas and Propagation 62, no. 1 (2014): 504–8. http://dx.doi.org/10.1109/tap.2013.2290536.
Full text
46
Triana, Johan F., Mauricio Arias, Jun Nishida, et al. "Semi-empirical quantum optics for mid-infrared molecular nanophotonics." Journal of Chemical Physics 156, no. 12 (2022): 124110. http://dx.doi.org/10.1063/5.0075894.
Full textAbstract:
Nanoscale infrared (IR) resonators with sub-diffraction limited mode volumes and open geometries have emerged as new platforms for implementing cavity quantum electrodynamics at room temperature. The use of IR nanoantennas and tip nanoprobes to study strong light–matter coupling of molecular vibrations with the vacuum field can be exploited for IR quantum control with nanometer spatial and femtosecond temporal resolution. In order to advance the development of molecule-based quantum nanophotonics in the mid-IR, we propose a generally applicable semi-empirical methodology based on quantum optics to describe light–matter interaction in systems driven by mid-IR femtosecond laser pulses. The theory is shown to reproduce recent experiments on the acceleration of the vibrational relaxation rate in infrared nanostructures. It also provides physical insights on the implementation of coherent phase rotations of the near-field using broadband nanotips. We then apply the quantum framework to develop general tip-design rules for the experimental manipulation of vibrational strong coupling and Fano interference effects in open infrared resonators. We finally propose the possibility of transferring the natural anharmonicity of molecular vibrational levels to the resonator near-field in the weak coupling regime to implement intensity-dependent phase shifts of the coupled system response with strong pulses and develop a vibrational chirping model to understand the effect. The semi-empirical quantum theory is equivalent to first-principles techniques based on Maxwell’s equations, but its lower computational cost suggests its use as a rapid design tool for the development of strongly coupled infrared nanophotonic hardware for applications ranging from quantum control of materials to quantum information processing.
47
Shan, Feng, Juan Tu, Jianchun Cheng, Dong Zhang, Faqi Li, and Zhibiao Wang. "Acoustic field of an ultrasonic cavity resonator with two open ends: Experimental measurements and lattice Boltzmann method modeling." Journal of Applied Physics 121, no. 12 (2017): 124502. http://dx.doi.org/10.1063/1.4978013.
Full text
48
Hammer, Manfred, Lena Ebers, and Jens Förstner. "Oblique evanescent excitation of a dielectric strip: A model resonator with an open optical cavity of unlimited Q." Optics Express 27, no. 7 (2019): 9313. http://dx.doi.org/10.1364/oe.27.009313.
Full text
49
Martí-Sabaté, Marc, Junfei Li, Djafari-Rouhani Bahram, A. Cummer Steven, and Daniel Torrent. "Observation of two-dimensional acoustic bound states in the continuum." Communications Physics (Commun Phys), no. 7 (April 9, 2024): 122. https://doi.org/10.1038/s42005-024-01615-8.
Full textAbstract:
The design of devices based on acoustic or optical fields requires the fabrication of cavities and structures capable of efficiently trapping these waves. A special type of cavity can be designed to support resonances with a theoretically infinite quality factor, named bound states in the continuum or BICs. The experimental measurement of such modes is still a challenging problem, as they are, by definition, not accessible from external perturbations. Here we report on the theoretical design and experimental realization of a two-dimensional, fully open acoustic resonator supporting BICs. This accidental BIC, whose symmetry is chosen during design by properly tailoring the geometrical properties of the system, is completely accessible and allows for the direct measurement of the whole pressure field and properties. We experimentally demonstrate its existence with high quality factor and field enhancement properties.
50
Barik, Rusan Kumar, Slawomir Koziel, and Anna Pietrenko-Dabrowska. "Broad Stopband, Low-Loss, and Ultra-Compact Dual-Mode Bandpass Filter Based on HMSIRC." Electronics 12, no. 13 (2023): 2831. http://dx.doi.org/10.3390/electronics12132831.
Full textAbstract:
In this investigation, an ultra-compact dual-mode bandpass filter (BPF) with a wide stopband response is realized by using a half-mode substrate-integrated rectangular cavity (HMSIRC). The HMSIRC resonator is designed with a cavity that is rectangular in shape and has metallic vias along three of the sides. The fourth side is open-ended and contains microstrip feed lines. For the purpose of constructing a magnetic wall, a rectangular slot is cut into each of the HMSIRC’s three edges. In order to produce an electrical wall that may generate a variety of resonances, the side with the open edges is provided with a single metallic via in the center. After that, a second-order BPF is generated by loading a transverse slot in the middle of the BPF, which enables independent frequency regulation of the mode frequencies. The eigen-mode analysis; field distributions; coupling matrix; and full-wave simulation of the proposed HMSIRC filter topology are used to develop the working principle of the filter. A second-order BPF is realized, constructed, and experimentally validated in order to provide evidence that the theory is correct. The BPF prototype achieves satisfactory performance thanks to its compact footprint of 0.028 λg2; its broad passband of 15.9%; its low insertion loss of 0.41 dB; and its wide stopband of 4.36 f0 with a rejection level greater than 20 dB. Both the measured and EM-simulated responses of the BPF are very consistent with one another.