Measurement of Permittivity of Ferroelectrics Using Coaxial Resonator

2011 ◽  
Vol 109 ◽  
pp. 195-198
Author(s):  
Biao Tan ◽  
Shu Bing Su
Keyword(s):  
Resonant Frequency ◽  
Numerical Method ◽  
Boundary Element ◽  
Thick Film ◽  
Coaxial Line ◽  
Experimental Results ◽  
Network Analyzer ◽  
Frequency Range ◽  
Fundamental Resonance ◽  
Coaxial Resonator

This paper presents a coaxial resonator technique applied for the measurement of the permittivity of ferroelectric thick film. A 1/4-wavelength coaxial resonator with appropriate dimensions were designed and made for measurements so that there is only TEM fundamental resonance in the interest frequency range. The permittivity may be extracted from the measured TEM fundamental resonant frequency in the resonator. The equivalent capacitance to the part between sample and open end of coaxial line is discussed, in which the boundary element numerical method was used for modeling the capacitance. The resonant frequency was measured using network analyzer and good experimental results were obtained.

scholarly journals Evaluation of a Reflection Method on an Open-Ended Coaxial Line and its Use in Dielectric Measurements

10.14311/882 ◽  
2006 ◽  
Vol 46 (5) ◽  
Author(s):  
R. Zajíček ◽  
J. Vrba ◽  
K. Novotný
Keyword(s):  
Biological Tissue ◽  
Tissue Sample ◽  
Coaxial Line ◽  
Dielectric Measurement ◽  
Network Analyzer ◽  
Reflection Method ◽  
Frequency Range ◽  
Discrete Elements ◽  
Biological Substance ◽  
Coaxial Probe

This paper describes a method for determining the dielectric constant of a biological tissue. A suitable way to make a dielectric measurement that is nondestructive and noninvasive for the biological substance and broadband at the frequency range of the network analyzer is to use a reflection method on an open ended coaxial line. A coaxial probe in the frequency range of the network analyzer from 17 MHz to 2 GHz is under investigation and also a calibration technique and the behavior of discrete elements in an equivalent circuit of an open ended coaxial line. Information about the magnitude and phase of the reflection coefficient on the interface between a biological tissue sample and a measurement probe is modeled with the aid of an electromagnetic field simulator. The numerical modeling is compared with real measurements, and a comparison is presented. 

scholarly journals Design and Fabrication of Modified SMA-Connector Sensor for Detecting Water Adulteration in Honey and Natural Latex

2021 ◽  
Vol 5 (1) ◽  
pp. 4
Author(s):  
Adisorn Nuan-On ◽  
Niwat Angkawisittpan ◽  
Nawarat Piladaeng ◽  
Chaiyong Soemphol
Keyword(s):  
Electrical Conductivity ◽  
Regression Analysis ◽  
Imaginary Part ◽  
Relative Permittivity ◽  
Detection System ◽  
Experimental Results ◽  
Network Analyzer ◽  
Frequency Range ◽  
Rubber Content ◽  
Phase Constant

A detection system for water adulteration in honey is proposed. It consists of a modified SMA-connector sensor and a vector network analyzer. A modified SMA-connector sensor is applied to measure complex relative permittivity, electrical conductivity, and phase constant of honey samples with the open-ended method. The system is tested in the frequency range of 0.5–4.0 GHz at the sample temperature of 25 °C. The relationships between the complex relative permittivity, electrical conductivity, the phase constant, and the honey samples with different concentrations (0–30%w/w) are determined. The experimental results show that the real part of the complex relative permittivity is significantly proportional in honey samples with adulteration of water in the range of 0–30%w/w. The frequency of 0.6 GHz is a suitable frequency for detection with a real part of complex relative permittivity as an indicator. The frequency of 3.74 GHz is an appropriate frequency for detection with electrical conductivity as in indicator while the frequency of 4.0 GHz is suitable for detection with phase constant as an indicator. In addition, the data are analyzed with regression analysis. This technique is also performed on natural latex samples to determine the dry rubber content. The frequency of 0.5 GHz is a suitable frequency with a real part of complex relative permittivity as an indicator while the frequency of 4.0 GHz is a suitable frequency with an imaginary part of complex relative permittivity, electrical conductivity, and phase constant as the indicators. The results demonstrate that it is possible to apply this technique to determine the dry rubber content in the natural latex samples as well.

Boundary element numerical method for the electric field generated by oblique multi-needle electrodes

2009 ◽  
Vol 52 (2) ◽  
pp. 189-197 ◽  
Author(s):  
FuPing Liu ◽  
AnLing Wang ◽  
AnXuan Wang ◽  
YueZu Cao ◽  
Qiang Chen ◽  
...  
Keyword(s):  
Electric Field ◽  
Numerical Method ◽  
Boundary Element

scholarly journals Simulation and Experimental Study of the Near Field Probe in the Form of a Folded Dipole for Measuring Glucose Concentration

2021 ◽  
Vol 11 (12) ◽  
pp. 5415
Author(s):  
Aleksandr Gorst ◽  
Kseniya Zavyalova ◽  
Aleksandr Mironchev ◽  
Andrey Zapasnoy ◽  
Andrey Klokov
Keyword(s):  
Experimental Measurement ◽  
Glucose Concentration ◽  
Field Experiments ◽  
Near Field ◽  
Vector Network Analyzer ◽  
Human Hand ◽  
Physical Parameters ◽  
Network Analyzer ◽  
Frequency Range ◽  
Average Deviation

The article investigates the near-field probe of a special design to account for changes in glucose concentration. The probe is designed in such a way that it emits radiation in both directions from its plane. In this paper, it was proposed to modernize this design and consider the unidirectional emission of the probe in order to maximize the signal and reduce energy loss. We have done extensive research for both bidirectional and unidirectional probe designs. Numerical simulations and field experiments were carried out to determine different concentrations of glucose (0, 4, 5.3, 7.5 mmol/L). Numerical modeling of a unidirectional probe showed that the interaction of radiation generated by such a probe with a multilayer structure simulating a human hand showed a better result and high sensitivity compared to a bidirectional probe. Further, based on the simulation results, a phantom (physical model) of a human hand was recreated from layers with dielectric properties as close as possible to the properties of materials during simulation. The probe was constructed from a copper tube and matched both the geometric and physical parameters of the model. The experimental measurement was carried out using a vector network analyzer in the frequency range 2–10 GHz. The experimental measurement was carried out using a vector network analyzer in the frequency range 2–10 GHz for the unidirectional and bidirectional probes. Further, the results of the experiment were compared with the results of numerical simulation. According to the results of multiple experiments, it was found that the average deviation between the concentrations was 2 dB for a unidirectional probe and 0.4 dB for a bidirectional probe. Thus, the sensitivity of the unidirectional probe was 1.5 dB/(mmol/L) for the bidirectional one 0.3 dB/(mmol/L). Thus, the improved design of the near-field probe can be used to record glucose concentrations.

Mechanical and Microwave Dielectric Properties of Csf/Si3N4 Composites

2007 ◽  
Vol 546-549 ◽  
pp. 1661-1664
Author(s):  
Xiao Yan Wang ◽  
Fa Luo ◽  
Dong Mei Zhu ◽  
Wan Cheng Zhou ◽  
Hong Huan Wu
Keyword(s):  
Carbon Fibers ◽  
Microwave Dielectric Properties ◽  
Xrd Analysis ◽  
Network Analyzer ◽  
Hot Press ◽  
Frequency Range ◽  
The Real ◽  
Microwave Dielectric ◽  
Hot Press Sintering ◽  
Sintering Method

Csf/Si3N4 composites were prepared by hot-press sintering method using α-Si3N4 power, short chopping carbon-fiber and sintering additives. XRD analysis showed that the α-Si3N4 was almost completely transferred into β-Si3N4. The SEM micrographs of fractured surfaces showed that special network developed by rod-like β- Si3N4 grains. The flexure strength of 590±10MPa, and fracture toughness of 7.94±0.1MPa·m1/2 were achieved for the samples incorporated with 0.5wt% the carbon fibers .The microwave dielectric property of Csf/Si3N4 composites was measured at a frequency range of 8.2~18GHz by E8362B PNA series network analyzer. The real part (ε ′ ) of the permittivity of the Csf/Si3N4 composites increases from 10 to 58 with the rise of the content of carbon fibers in the composites, as well as the imaginary part increases from 0.03 to 98 at frequency of 9.375GHz. A strong frequency dependence of the real part was observed both in X and Ku bands.

Study on a Novel MEMS High G Acceleration Sensor

2012 ◽  
Vol 490-495 ◽  
pp. 499-503
Author(s):  
Ping Li ◽  
Yun Bo Shi ◽  
Jun Liu ◽  
Shi Qiao Gao
Keyword(s):  
Resonant Frequency ◽  
Natural Frequency ◽  
Impact Load ◽  
Hopkinson Bar ◽  
Experimental Results ◽  
Structure Parameters ◽  
Acceleration Sensor ◽  
Piezoresistive Effect ◽  
Sensor Structure ◽  
The Impact

This paper presents a novel MEMS high g acceleration sensor based on piezoresistive effect. For the designed sensor structure, the formula of stress, natural frequency and damping was derived in theory, and the resonant frequency can up to 500kHz. After the structure parameters were designed, the sensor was fabricated by the standard processing technology, and the sensitivity was tested by Hopkinson bar. According to the experimental results, the sensitivity of the high g acceleration sensor is 0.125μV/g at the impact load of 164,002g.

Boundary Element Method Used in Random Response Calculation of the Plate-Beam Structure

1991 ◽  
Author(s):  
J. M. Zhu ◽  
L. Huang
Keyword(s):  
Boundary Element Method ◽  
Numerical Method ◽  
Boundary Element ◽  
Pressure Fluctuation ◽  
Random Vibration ◽  
Power Plants ◽  
Measured Data ◽  
Random Response ◽  
Beam Structure ◽  
Element Method

Abstract The furnace walls of the large boilers in power plants are combined structures consisting of orthotopic plate and equally spaced beams, which are usually submitted to random vibration under the excitation of the pressure fluctuation induced by combustion in the furnace. In this paper, a numerical method based on BEM to compute the random response of the structure is offered. The agreement between the computing results and the measured data in a practical example verifies the effectiveness of the method.

scholarly journals Application of hybrid boundary element method: Example of semishperical ground inhomogeneity

2014 ◽  
Vol 11 (4) ◽  
pp. 617-628
Author(s):  
Nenad Cvetkovic ◽  
Sasa Ilic ◽  
Dragan Vuckovic ◽  
Dejan Jovanovic ◽  
Dejan Krstic
Keyword(s):  
Boundary Element Method ◽  
Point Source ◽  
Numerical Method ◽  
Boundary Element ◽  
Program Package ◽  
Image Theory ◽  
Field Analysis ◽  
Grounding System ◽  
Em Field ◽  
Element Method

One new, so-called hybrid boundary element method (HBEM) is presented in this paper. It is a recently proposed numerical method for stationary and quasi-stationary EM field analysis. The method application is illustrated on the example of solving the problem of modelling hemispherical ground inhomogeneity influence on grounding system. The applied procedure also includes using of quasi-stationary image-theory. The obtained results are compared with those ones based on using the Green?s function for the point source inside semi-spherical inhomogeneities as well as with the results obtained by applying COMSOL program package.

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