THEORY AND DESIGN OF A COAXIAL SUPPORTING BEAD MADE OF COMPOSITE DIELECTRICS

1961 ◽  
Vol 39 (6) ◽  
pp. 926-934
Author(s):  
Gilbert H. Owyang
Keyword(s):  
Standing Wave ◽  
Frequency Ratio ◽  
Low Voltage ◽  
Coaxial Line ◽  
Wide Band ◽  
Voltage Standing Wave Ratio ◽  
Physical Parameters ◽  
Minimum Frequency ◽  
Typical Design

The effect due to the presence of a single supporting bead made of composite dielectrics in a coaxial line is being studied. A formula correlating the standing wave ratio caused by the bead and the physical parameters of the bead is derived. A bead of this type may be designed to have very low voltage standing wave ratio (VSWR) over a very wide band of frequency. A typical design using quartz and air as dielectrics is given, and the calculated VSWR is below 1.003 over a bandwidth whose maximum to minimum frequency ratio is as high as 13:1.

Fabrication of Horn Antenna for Microwave Application

2020 ◽  
Vol 6 (2) ◽  
pp. EC-17-EC-27
Author(s):  
Yusuf Durachman ◽  
Keyword(s):  
Standing Wave ◽  
Power Transmission ◽  
Low Voltage ◽  
Horn Antenna ◽  
High Gain ◽  
Transmission Efficiency ◽  
Voltage Standing Wave Ratio ◽  
Microwave Application ◽  
Microwave Applications ◽  
Novel Design

This paper contains a novel design of a horn antenna control system for microwave applications. Using “Fermat’s principle” the horn antenna is designed and fabricated. For microwave applications, high gain and low voltage standing wave ratio(VSWR) is needed, so for that purpose horn antenna is fabricated. In a previous paper, they designed the Yagi Uda antenna which is used for multiple driven elements by the method called maximum power transmission efficiency. For multiple driven elements, the horn antenna cannot be fabricated. If suppose yagi uda is fabricated using the principle called Fermat's, the system can't achieve more gain and low voltage standing wave ratio. Yagi uda antenna can achieve only a high voltage standing wave ratio. To reduce the problems in the existing paper, our paper designs a horn antenna to achieve high gain and low voltage standing wave ratio( VSWR) which is used for microwave applications to transmit microwaves from a waveguide out into space or collect microwaves into a waveguide for the reception.

Design of a compact wide band microstrip antenna with very low VSWR for WiMAX applications

2016 ◽  
Vol 9 (3) ◽  
pp. 685-690 ◽  
Author(s):  
Aparna Kundu ◽  
Ujjal Chakraborty ◽  
Anup Kumar Bhattacharjee
Keyword(s):  
Standing Wave ◽  
Microstrip Antenna ◽  
Low Voltage ◽  
Single Layer ◽  
Wide Band ◽  
Center Frequency ◽  
Computational Results ◽  
Measurement Results ◽  
Rectangular Microstrip Antenna ◽  
Peak Gain

A single-layer coaxial-fed compact rectangular microstrip antenna with very low voltage standing wave ratio (VSWR) is presented in this paper. The simulated VSWR of the proposed antenna 1.00374 is obtained near the center frequency of the operating band (3.5 GHz). Simulation and measurement results indicate that the bandwidth (simulated: 3.36–3.715 GHz, and measured: 3.295–3.645 GHz) of the antenna exceeds 10% below VSWR 2, when the size reduction of the antenna is about 81.6%. The realized peak gain is obtained about 2.15 dBi at 3.5 GHz. For the verification of the computational results, two designs were fabricated and measured. Good agreements between simulated and measured results were found.

Broadband “in-series multistation” rf cavity with low voltage standing wave ratio

2005 ◽  
Vol 76 (5) ◽  
pp. 053306
Author(s):  
Toshiyuki Misu ◽  
Nobuyuki Miyahara ◽  
Akinori Sugiura ◽  
Satoru Hojo ◽  
Mitsutaka Kanazawa ◽  
...  
Keyword(s):  
Standing Wave ◽  
Low Voltage ◽  
Voltage Standing Wave Ratio ◽  
Rf Cavity ◽  
In Series

Research of Possibilities of Using the Recycled Materials Based on Rubber and Textiles Combined with Vermiculite Material in the Area of ​​Noise Reduction

2014 ◽  
Vol 1001 ◽  
pp. 171-176 ◽  
Author(s):  
Pavol Liptai ◽  
Marek Moravec ◽  
Miroslav Badida
Keyword(s):  
Absorption Coefficient ◽  
Standing Wave ◽  
Sound Pressure Level ◽  
Sound Absorption ◽  
Sound Pressure ◽  
Sound Level ◽  
Pressure Level ◽  
Sound Absorption Coefficient ◽  
Physical Parameters ◽  
Materials Research

This paper describes possibilities in the use of recycled rubber granules and textile materials combined with vermiculite panel. The aim of the research is the application of materials that will be absorbing or reflecting sound energy. This objective is based on fundamental physical principles of materials research and acoustics. Method of measurement of sound absorption coefficient is based on the principle of standing wave in the impedance tube. With a sound level meter is measured maximum and minimum sound pressure level of standing wave. From the maximum and minimum sound pressure level of standing wave is calculated sound absorption coefficient αn, which can take values from 0 to 1. Determination of the sound absorption coefficient has been set in 1/3 octave band and in the frequency range from 50 Hz to 2000 Hz. In conclusion are proposed possibilities of application of these materials in terms of their mechanical and physical parameters.

Design of Antipodal Vivaldi Antenna Array

2013 ◽  
Vol 380-384 ◽  
pp. 3465-3468
Author(s):  
Hai Bo Tang ◽  
Xiao Zhong Shui
Keyword(s):  
Antenna Array ◽  
Standing Wave ◽  
Voltage Standing Wave Ratio ◽  
Radiation Characteristics ◽  
Vivaldi Antenna ◽  
Cross Structure ◽  
Structure Array

Firstly in this paper,an antipodal Vivaldi antenna is designed.The bandwidth is from 6GHz to 18GHz. The simulated results show good electric performance and the voltage standing wave ratio is less than 2 in the whole bandwidth.Secondly depending on this unit,this paper designs two kinds of arrays and estimates their radiation characteristics,respectively.The one array is a 1×8 array and the another array is a X-cross structure array with four elements.

GROUNDING EFFECT ON THE PERFORMANCE OF UWB ICE-CREAM CONE ANTENNA

2016 ◽  
Vol 78 (5-10) ◽  
Author(s):  
Siti Rohmah Mohamed Kamaruddin ◽  
Ahmad Rakimi Mohamed ◽  
Abu Bakar Ibrahim
Keyword(s):  
Dielectric Constant ◽  
Standing Wave ◽  
Ice Cream ◽  
Voltage Standing Wave Ratio ◽  
Planar Antenna ◽  
Radiation Characteristics ◽  
Dielectric Thickness ◽  
Antenna Performance ◽  
Spectrum Band ◽  
Cst Microwave Studio

In this paper, presents the grounding effect on the performance of UWB Ice Cream Cone Antenna communication. This planar antenna designed on a FR4 substrate with the dielectric thickness, 1.6 mm and the dielectric constant Ɛr, 4.7. An analysis results for antenna with different parameter for width of feed as a ground has been investigated. The antennas were designed and simulated by using CST Microwave Studio Simulation. The proposed antenna performs from 4 GHz to 11 GHz spectrum band. The return losses, S11 for the suggestion antenna must be below than -10dB and voltage standing wave ratio, VSWR less than 2. The best grounded single ice cream cone antenna performance was obtained at 5.688 GHz with antenna sizes is 12 mm x 14.5 mm. The antenna gives omnidirectional radiation characteristics from UWB spectrum band requirement with reasonable gain values.

THE COMPLEX DIELECTRIC CONSTANT OF SOLUTIONS OF TRIMETHYLPENTANE AND NITROBENZENE NEAR THE CONSOLUTE TEMPERATURE

1961 ◽  
Vol 39 (3) ◽  
pp. 526-534 ◽  
Author(s):  
B. D. Ripley ◽  
R. McIntosh
Keyword(s):  
Dielectric Constant ◽  
Phase Separation ◽  
Standing Wave ◽  
Applied Field ◽  
Coaxial Line ◽  
Dielectric Constants ◽  
Complex Dielectric Constant ◽  
Experimental Procedure ◽  
Chemical Systems ◽  
Consolute Temperature

The complex dielectric constants of three compositions of trimethylpentane and nitrobenzene have been measured as a function of temperature for a range near the consolute temperature. The frequency employed was 3300 Mc/sec. The experimental procedure involved the study of the standing wave established in a coaxial line. The chemical systems showed maxima in both the real and imaginary parts of the complex dielectric constant at temperatures above those at which phase separation occurs. The finding of Semenchenko and Azimov is thus confirmed. A discussion of the validity of applying thermodynamic formulae to dielectrics showing loss is given and some qualitative remarks are offered concerning the change of the systems as they are cooled. These remarks are based upon the effect of the applied field upon the entropy of the solutions.

International comparison of low voltage (0.001 V) and high voltage (100 V) in coaxial line at 30 MHz

1995 ◽  
Vol 44 (2) ◽  
pp. 312-315
Author(s):  
D. Janik ◽  
X. De-Xiong ◽  
J.T. Valkeapaa ◽  
G. Rebuldela ◽  
V.K. Rustagi ◽  
...  
Keyword(s):  
International Comparison ◽  
High Voltage ◽  
Low Voltage ◽  
Coaxial Line

Alternative solution to the gamma bench for the dielectric characterization of materials

2020 ◽  
Author(s):  
Imen boughanmi ◽  
Cyrille Fauchard ◽  
Nabil Benjelloun ◽  
Zouheir Riah
Keyword(s):  
Relative Permittivity ◽  
Wide Band ◽  
Cylindrical Sample ◽  
Cost Ratio ◽  
Physical Parameters ◽  
Dielectric Characterization ◽  
Density Control ◽  
Technical Specifications ◽  
Characterization Of Materials ◽  
The Time Domain

<p>In the field of civil engineering, and more particularly in the road building, it is necessary to control some physical parameters with standard methods. These controls ensure the implementation is performed according to the technical specifications. They also allow to optimize the structure dimensions  with the best safety/cost ratio and an optimal lifetime. Compactness related to density and therefore indicative of mechanical strength necessary to support traffic solicitations is a key parameter to control. Currently, density control in the laboratory is done using bench with nuclear sources on pavement cores, based on the emission and reception of gamma rays. Its replacement has now become a major issue since this method generates increasingly high costs and constraints (use, storage, transport and exposure to ionizing radiation). The objective of this work is to find an alternative non-nuclear solution to control the pavement compactness with an accuracy equivalent to the gamma-bench method . The proposed solution is an electromagnetic bench (EM), allowing cores tomography to measure permittivity. The density will then be evaluated by means of mixing rules. The EM bench consists of a vector network analyzer (Agilent E8362B) and two Ultra-Wide Band antennas [1.4-15 GHz] which are developed in this project in order to have the best performances (accuracy, dimensions…).</p><p>The antennas are placed facing each other, separated by a distance D.  A cylindrical sample (core) extracted from stratified road medium of diameter d to be tested is placed in the middle of the system and both antennas move with a given step (ranging from a few mm to 1 cm) along the sample to measure by stratification the core EM properties. The entire EM bench is motorized and driven by software developed in the laboratory. At each step, a measurement of S<sub>21</sub> -parameter is recorded. Then signals are processed in the time domain to evaluate the relative permittivity.</p><p>The first results of modeling and measurements on laboratory asphalt samples show that the system makes it possible to evaluate the relative permittivity of different stratified materials. Accuracy, resolution and perspectives will be discussed.</p><p>key words : density, asphalt concrete, radar, electromagnetic bench</p>

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