scholarly journals Highly Sensitive Reflective-Mode Defect Detectors and Dielectric Constant Sensors Based on Open-Ended Stepped-Impedance Transmission Lines

Sensors ◽  
2020 ◽  
Vol 20 (21) ◽  
pp. 6236
Author(s):  
Pau Casacuberta ◽  
Jonathan Muñoz-Enano ◽  
Paris Vélez ◽  
Lijuan Su ◽  
Marta Gil ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Transmission Line ◽  
Transmission Lines ◽  
Characteristic Impedance ◽  
Reference Sample ◽  
Phase Variation ◽  
Dielectric Constants ◽  
High Impedance ◽  
Line Section ◽  
Highly Sensitive

In this paper, reflective-mode phase-variation sensors based on open-ended stepped-impedance transmission lines with optimized sensitivity for their use as defect detectors and dielectric constant sensors are reported. The sensitive part of the sensors consists of either a 90° high-impedance or a 180° low-impedance open-ended sensing line. To optimize the sensitivity, such a sensing line is cascaded to a 90° transmission line section with either low or high characteristic impedance, resulting in a stepped-impedance transmission line configuration. For validation purposes, two different sensors are designed and fabricated. One of the sensors is implemented by means of a 90° high impedance (85 Ω) open-ended sensing line cascaded to a 90° low impedance (15 Ω) transmission line section. The other sensor consists of a 180° 15-Ω open-ended sensing line cascaded to a 90° 85-Ω line. Sensitivity optimization for the measurement of dielectric constants in the vicinity of that corresponding to the Rogers RO4003C substrate (i.e., with dielectric constant 3.55) is carried out. The functionality as a defect detector is demonstrated by measuring the phase-variation in samples consisting of the uncoated Rogers RO4003C substrate (the reference sample) with arrays of holes of different densities.

scholarly journals A Novel Synthetization Approach for Multi Coupled Line Section Impedance Transformers in Wideband Applications

2022 ◽  
Vol 12 (2) ◽  
pp. 875
Author(s):  
Nan Zhang ◽  
Xiaolong Wang ◽  
Chunxi Bao ◽  
Bin Wu ◽  
Chun-Ping Chen ◽  
...  
Keyword(s):  
Transmission Lines ◽  
Return Loss ◽  
Circuit Simulation ◽  
Characteristic Impedance ◽  
Fractional Bandwidth ◽  
Coupled Line ◽  
Variable Parameters ◽  
Line Section ◽  
Original Topology ◽  
Impedance Parameters

In this paper, a novel synthetization approach is proposed for filter-integrated wideband impedance transformers (ITs). The original topology consists of N cascaded coupled line sections (CLSs) with 2N characteristic impedance parameters. By analyzing these characteristic impedances, a Chebyshev response can be derived to consume N + 2 design conditions. To optimize the left N − 2 variable parameters, CLSs were newly substituted by transmission lines (TLs) to consume the remaining variable parameters and simplify the circuit topology. Therefore, there are totally 2N − N − 2 substituting possibilities. To verify the proposed approach, 25 cases are listed under the condition of N = 5, and 7 selected cases are compared and discussed in detail. Finally, a 75–50 Ω IT with 100% fractional bandwidth and 20 dB bandpass return loss (RL) is designed and fabricated. The measured results meet the circuit simulation and the EM simulation accurately.

Transmission Line

2020 ◽  
pp. 43-71
Keyword(s):  
Transmission Line ◽  
Transmission Lines ◽  
Magnetic Energy ◽  
Propagation Constant ◽  
Characteristic Impedance ◽  
Electric Energy ◽  
Electromagnetic Energy ◽  
The Other ◽  
Electrical Characteristics ◽  
Lumped Elements

A transmission line (TL) is simply a medium that is capable of guiding or propagating electromagnetic energy. The transmission line stores the electric (E) and magnetic (M) energies and distributes them in space by alternating them between the two forms. This means that at any point along a TL, energy is stored in a mixture of E and M forms and, for an alternating signal at any point on the TL, converted from one form to the other as time progresses. Transmission line is usually modelled using lumped elements (i.e., inductors for magnetic energy, capacitors for electric energy, and resistors for modelling losses). The electrical characteristics of a TL such as the propagation constant, the attenuation constant, the characteristic impedance, and the distributed circuit parameters can only be determined from the knowledge of the fields surrounding the transmission line. This chapter gives a brief overview of various transmission lines, with more detailed discussions on the microstrip and the SIW.

scholarly journals Solving the Complexity Problem in the Electronics Production Process by Reducing the Sensitivity of Transmission Line Characteristics to Their Parameter Variations

Complexity ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Talgat R. Gazizov ◽  
Indira Ye. Sagiyeva ◽  
Sergey P. Kuksenko
Keyword(s):  
Transmission Line ◽  
Production Process ◽  
Transmission Lines ◽  
Unit Length ◽  
Characteristic Impedance ◽  
Optimal Choice ◽  
Wide Range ◽  
Complexity Problem ◽  
Parameter Variations ◽  
Parameter Values

In this paper we consider the complexity problem in electronics production process. Particularly, we investigate the ways to reduce sensitivity of transmission line characteristics to their parameter variations. The reduction is shown for the per-unit-length delay and characteristic impedance of several modifications of microstrip transmission lines. It can be obtained by means of making an optimal choice of parameter values, enabling proper electric field redistribution in the air and the substrate. To achieve this aim we used an effective simulation technique and software tools. Taken together, for the first time, they have allowed formulating general approach which is relevant to solve a wide range of similar tasks.

Defect-Induced Properties of Doped Alpha Alumina Samples

2008 ◽  
Vol 55-57 ◽  
pp. 801-804 ◽  
Author(s):  
P. Jantaratana ◽  
Pisutti Dararutana ◽  
Wiwat Wongkokua ◽  
Sorapong Pongkrapan ◽  
P. Wathanakul
Keyword(s):  
Dielectric Constant ◽  
Parallel Plate ◽  
Reference Sample ◽  
Dielectric Constants ◽  
Refractive Indices ◽  
Plate Method ◽  
Physico Chemical ◽  
Voltage Frequency ◽  
Chemical Conditions ◽  
Alpha Alumina

The dielectric constant values of a set of synthetic alpha alumina samples doped with Cr and Be were determined using parallel plate method. The voltage frequency was selected at 1 MHz. When Cr was doped to the sample, the dielectric constant was increased due to the increase in polarizations of the sample, whereas the Be-doped one showed the decrease in dielectric constant cf. the undoped synthetic alpha alumina (reference sample). Experiments on doping alpha alumina with both elements showed increasing in dielectric constant compared to the undoped reference sample, i.e., Cr has more influence to the dielectric constant value. Dielectric constants of a set of natural sapphires were also measured and compared to those obtained from the synthetic ones. The results of both natural and synthetic samples varied in the same direction. It suggests, however, that the geological origins of the samples are needed to be considered. This is due to the differences in physico-chemical conditions of their formations that would have influenced partitioning of trace elements as well as evolving of defects in natural samples. Increasing of the R1 and R2 photoluminescence wavelengths and decreasing of refractive indices of the doped samples cf. those of the reference sample were obtained from the experiments.

scholarly journals Analytical Model for High Impedance Fault Analysis in Transmission Lines

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
S. Maximov ◽  
V. Torres ◽  
H. F. Ruiz ◽  
J. L. Guardado
Keyword(s):  
Transmission Line ◽  
Analytical Model ◽  
Transmission Lines ◽  
Fire Hazard ◽  
Human Life ◽  
Electric Arc ◽  
Fault Analysis ◽  
Arc Model ◽  
High Impedance ◽  
High Impedance Fault

A high impedance fault (HIF) normally occurs when an overhead power line physically breaks and falls to the ground. Such faults are difficult to detect because they often draw small currents which cannot be detected by conventional overcurrent protection. Furthermore, an electric arc accompanies HIFs, resulting in fire hazard, damage to electrical devices, and risk with human life. This paper presents an analytical model to analyze the interaction between the electric arc associated to HIFs and a transmission line. A joint analytical solution to the wave equation for a transmission line and a nonlinear equation for the arc model is presented. The analytical model is validated by means of comparisons between measured and calculated results. Several cases of study are presented which support the foundation and accuracy of the proposed model.

scholarly journals Applying the Retarded Solutions of Electromagnetic Fields to Transmission Line RLGC Modeling

2017 ◽  
Vol 6 (1) ◽  
pp. 56
Author(s):  
P. Ye ◽  
B. Gore ◽  
P. Huray
Keyword(s):  
Transmission Line ◽  
Transmission Lines ◽  
Analytical Approach ◽  
Propagation Constant ◽  
Unit Length ◽  
Characteristic Impedance ◽  
Simulation Methods ◽  
Arbitrary Length ◽  
Small Segment ◽  
Numerical Simulation Methods

The RLGC model, and its variations, is one of the most common techniques to simulate Transmission Lines. The RLGC model uses circuit network elements consisting of Resistance R, Inductance L, Conductance G and Capacitance C (per unit length) to represent a small segment of the Transmission Line, and then cascades multiple segments to simulate the Transmission Line of arbitrary length. Typically the parameters in RLGC model are extracted from the propagation constant and characteristic impedance of the transmission line, which are found using numerical simulation methods. These resulting RLGC parameters for multi-GHz signaling are usually frequency-dependent. This paper introduces an analytical approach to extract RLGC parameters to simulate transmission line, which results in a different model, the RLGC(p) model.

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