Frequency Dependence of the Coupling Coefficients and Resonant Frequency Detuning in a Nanophotonic Waveguide-Cavity System

Organic coverlays are required to protect microstrip circuits in most applications. The presence of coverlay can potentially influence the performance of microstrip antennas. This paper describes the qualification of polyimide based coverlays for microstrip antennas both in 900 MHz and 2.50 GHz frequency bands. An Inverted F-shaped antenna fabricated on FR-4 dielectric is used as the test vehicle and two different coverlay materials are tested with respect to key parameters like resonant frequency, S11 bandwidth, antenna gain, frequency detuning, and radiation pattern. The data presented in this paper clearly indicates polyimide materials are well suited to cover microstrip antenna circuits with minimal impact on performance.

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Total respiratory input and transfer impedances in humans

Journal of Applied Physiology ◽

10.1152/jappl.1985.59.2.492 ◽

1985 ◽

Vol 59 (2) ◽

pp. 492-501 ◽

Cited By ~ 40

Author(s):

R. Peslin ◽

C. Duvivier ◽

C. Gallina

Keyword(s):

Resonant Frequency ◽

Frequency Dependence ◽

Imaginary Part ◽

Airway Resistance ◽

The Real ◽

Tissue Resistance ◽

Gas Compressibility ◽

Healthy Males

Total respiratory input (Zrs,in) and transfer (Zrs,tr) impedances were obtained from 4 to 30 Hz in 10 healthy males by simultaneously measuring mouth and chest flow while applying pseudo-random pressure variations at the mouth. Compared with Zrs,in, the real part of Zrs,tr was larger up to 10 Hz but exhibited a much stronger negative frequency dependence. The imaginary part was larger at all frequencies, with a resonant frequency (fn) at 6.0 +/- 0.8 Hz compared with 8.2 +/- 2.9 Hz for Zrs,in. The two impedances were analyzed with a model featuring airway resistance and inertance, alveolar gas compressibility, and tissue resistance, inertance, and compliance. A good fit was generally obtained but, in most cases, with a different partitioning of resistance between airway and tissue for Zrs,in and Zrs,tr. The data were also used to compute separately airway and tissue (Zt) impedances. In most subjects Zt could not be properly fitted with a simple resistance-inertance-compliance unit and was consistent with a slow (fn = 7.4 +/- 2.3 Hz) overdamped compartment in parallel with a fast (fn = 37.1 +/- 5.6 Hz) underdamped one.

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Excitation of a taylor vortex mode having resonant frequency dependence of coherence length

Physics Letters A ◽

10.1016/0375-9601(82)90665-x ◽

1982 ◽

Vol 88 (8) ◽

pp. 407-409 ◽

Cited By ~ 2

Author(s):

A. Brandstäter ◽

G. Pfister ◽

E.O. Schulz-DuBois

Keyword(s):

Resonant Frequency ◽

Frequency Dependence ◽

Coherence Length ◽

Taylor Vortex

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Systematic Theoretical Analysis of Dual-Parameters RF Readout by a Novel LC-Type Passive Sensor

Modelling and Simulation in Engineering ◽

10.1155/2017/4938732 ◽

2017 ◽

Vol 2017 ◽

pp. 1-11

Author(s):

Qiulin Tan ◽

Yanjie Guo ◽

Guozhu Wu ◽

Tao Luo ◽

Tanyong Wei ◽

...

Keyword(s):

Theoretical Analysis ◽

Resonant Frequency ◽

Influencing Factors ◽

Theoretical Perspective ◽

Signal Strength ◽

Design Guidelines ◽

Frequency Interval ◽

Coupling Coefficients ◽

Passive Sensor ◽

Signal Crosstalk

This paper systematically studied the simultaneous measurement of two parameters by a LC-type passive sensor from the theoretical perspective. Based on the lumped circuit model of the typical LC-type passive dual-parameter sensor system, the influencing factors of the signal strength of the sensor as well as the influencing factors of signal crosstalk were both analyzed. It is found that the influencing factors of the RF readout signal strength of the sensor are mainly quality factors (Q factors) of the LC tanks, coupling coefficients, and the resonant frequency interval of the two LC tanks. And the influencing factors of the signal crosstalk are mainly coupling coefficient between the sensor inductance coils and the resonant frequency interval of the two LC tanks. The specific influence behavior of corresponding influencing factors on the signal strength and crosstalk is illustrated by a series of curves from numerical results simulated by using MATLAB software. Additionally, a decoupling scheme for solving the crosstalk problem algorithmically was proposed and a corresponding function was derived out. Overall, the theoretical analysis conducted in this work can provide design guidelines for making the dual-parameter LC-type passive sensor useful in practical applications.

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Resonant frequency dependence of spin relaxation in concentrated metallic spin glasses

Physical Review B ◽

10.1103/physrevb.33.2070 ◽

1986 ◽

Vol 33 (3) ◽

pp. 2070-2072 ◽

Cited By ~ 15

Author(s):

M. J. Park ◽

S. M. Bhagat ◽

M. A. Manheimer ◽

K. Moorjani

Keyword(s):

Resonant Frequency ◽

Frequency Dependence ◽

Spin Relaxation ◽

Spin Glasses

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Frequency Dependence on Image Reconstruction for a Buried Conducting Cylinder

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.284-287.473 ◽

2013 ◽

Vol 284-287 ◽

pp. 473-477

Author(s):

Wei Chien ◽

Hsien Wei Tseng ◽

Yung Wen Lee ◽

Liang Yu Yen ◽

Chien Ching Chiu

Keyword(s):

Genetic Algorithm ◽

Steady State ◽

Image Reconstruction ◽

Resonant Frequency ◽

Frequency Dependence ◽

Incident Wave ◽

Optimization Problem ◽

Quantitative Information ◽

Frequency Range ◽

Conducting Cylinder

Frequency dependence on image reconstruction for a buried conducting cylinder is investigated. A conducting cylinder of unknown shape scatters the incident wave in free space and measured the scattered field. By using measured fields, the imaging problem is reformulated into an optimization problem and solved by the steady-state genetic algorithm (SSGA). Numerical results show that the reconstruction is quite well in the resonant frequency range. This work provides both comparative and quantitative information

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Composite pulses for high fidelity population transfer in three-level systems

New Journal of Physics ◽

10.1088/1367-2630/ac48e7 ◽

2022 ◽

Author(s):

Zhicheng Shi ◽

Cheng Zhang ◽

Du Ran ◽

Yan Xia ◽

Reuven Ianconescu ◽

...

Keyword(s):

Cost Function ◽

Singlet State ◽

Transition Probability ◽

Pulse Sequences ◽

High Fidelity ◽

Population Transfer ◽

Coupling Coefficients ◽

Cavity System ◽

Waveform Distortions ◽

Composite Pulses

Abstract In this work, we propose a composite pulses scheme by modulating phases to achieve high fidelity population transfer in three-level systems. To circumvent the obstacle that not enough variables are exploited to eliminate the systematic errors in the transition probability, we put forward a cost function to find the optimal value. The cost function is independently constructed either in ensuring an accurate population of the target state, or in suppressing the population of the leakage state, or both of them. The results demonstrate that population transfer is implemented with high fidelity even when existing the deviations in the coupling coefficients. Furthermore, our composite pulses scheme can be extensible to arbitrarily long pulse sequences. As an example, we employ the composite pulses sequence for achieving the three-atom singlet state in an atom-cavity system with ultrahigh fidelity. The final singlet state shows robustness against deviations and is not seriously affected by waveform distortions. Also, the singlet state maintains a high fidelity under the decoherence environment.

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