ALGORITHM FOR CALCULATING SURFACES OF BIFOCAL LENS ANTENNAS

2019 ◽  
pp. 53-59
Author(s):  
Yu. S. Nikulina
Keyword(s):  
Dielectric Constant ◽  
Analytical Solution ◽  
Optical Axis ◽  
Relative Dielectric Constant ◽  
Phase Front ◽  
Systems Of Equations ◽  
Lens Antenna ◽  
Electrical Length ◽  
Lens Antennas ◽  
In Series

An algorithm is proposed that makes it possible to calculate the coefficients of power polynomials approximating the illuminated and shadow surfaces of bifocal lens antennas. The algorithm is based on providing equality of electrical lengths of rays passing from the focus points through lens body and its edge and on the assumption that the phase front is flat and is inclined at a determined angle relative to the main optical axis of the lens on the aperture of the lens antenna. For each of the rays an expression was written that determines its electrical length. The electrical length of the rays depends on the points coordinates of the illuminated and shadow surface of the lens, in which they are refracted. The analytical solution of the obtained equation is difficult. Therefore, it is proposed to determine the exact coordinate values by numerical methods. The proposed algorithm determines in series the three points lying on the illuminated and shadow surfaces. The coordinates of the points are used to form systems of equations whose solutions are the coefficients of power polynomials approximating the illuminated and shadow surfaces of the lens antenna. The algorithm does not impose restrictions on the relative dielectric constant of the material from which the lens antenna is made.

Effect Of Moisture On The Physical Properties Of Polyimide Films

1991 ◽  
Vol 227 ◽  
Author(s):  
Rajeevi Subramanian ◽  
Michael T. Pottiger ◽  
Jacqueline H. Morris ◽  
Joseph P. Curilla
Keyword(s):  
Dielectric Constant ◽  
Steady State ◽  
Electrical Properties ◽  
Relative Humidity ◽  
Quartz Crystal ◽  
Moisture Absorption ◽  
Relative Dielectric Constant ◽  
Moisture Uptake ◽  
Polyimide Films ◽  
Effect Of Moisture

ABSTRACTMoisture absorption and its effect on electrical properties were measured for several polyimides. A Quartz Crystal Microbalance (QCM) was used to investigate the moisture absorption in BPDA/PPD, PMDA/ODA, and BTDA//ODA/MPD polyimides. The steady-state moisture uptake in polyimides as a function of relative humidity (RH) was determined by exposing film samples to successively higher RH values ranging from 10 to 85% at 25°C. The isothermal moisture absorption as a function of percent RH was found to be nearly linear for all of the polyimides studied. The effect of moisture on the electrical properties of a BPDA/PPD polyimide was also investigated. The relative dielectric constant at 25 °C was found to be a linear function of the moisture absorbed.

The Research on the Piezoelectric and Dielectric Properties of Bi0.5(Nak)0.5-BaTiO3 Lead-Free Ceramics

2014 ◽  
Vol 1035 ◽  
pp. 422-425
Author(s):  
Jian Yong Guo ◽  
Tao Sheng Zhou ◽  
Ji Hong Liao
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Perovskite Structure ◽  
Relative Dielectric Constant ◽  
Lead Free ◽  
Reactive Sintering ◽  
Lead Free Ceramics ◽  
Xrd Patterns ◽  
Sintering Method

The Bi0.5(Na1-xKx)0.5-yBaTiO3(BNK-BT) lead-free ceramics have been prepared by the solild reactive sintering method. XRD patterns show the BNK-BT ceramics had a perovskite structure. Piezoelectric and dielectric properties of the ceramics also have been studied. The results show that the samples had the best piezoelectric and dielectric properties when x=0.20, y=0.10. And the maximum of d33is 149 pC/N, while the relative dielectric constant is 1087.

The Processing and Properties of Multilayer Interconnection Structures Using Thermoset Films Derived from Bisbenzocyclobutene.

1989 ◽  
Vol 154 ◽  
Author(s):  
P. H. Townsend ◽  
D. C. Burdeaux ◽  
S. F. Hahn ◽  
M. Thomsen ◽  
J. N. Carr
Keyword(s):  
Dielectric Constant ◽  
Thermal Cycling ◽  
Relative Dielectric Constant ◽  
Electrical Characteristics ◽  
Processing Conditions ◽  
Dielectric Layers ◽  
Significant Change

AbstractMultilayer interconnection structures incorporating a novel polymeric dielectric derived from a bis-benzocyclobutene(bis-BCB) monomer have been fabricated. This paper discusses the processing conditions for the construction of these circuits and describes electrical characteristics of the dielectric layers. The relative dielectric constant of the BCB film was 2.7. Thermal cycling produced no significant change in the conductance of three level metal via chains through two layers of the polymer.

scholarly journals Experimental Study on the Icing Dielectric Constant for the Capacitive Icing Sensor

Sensors ◽  
2018 ◽  
Vol 18 (10) ◽  
pp. 3325
Author(s):  
Yongcan Zhu ◽  
Xinbo Huang ◽  
Yi Tian ◽  
Chao Ji ◽  
Wen Cao ◽  
...  
Keyword(s):  
Experimental Study ◽  
Dielectric Constant ◽  
Test Temperature ◽  
Reference Value ◽  
Relative Dielectric Constant ◽  
Capacitive Sensor ◽  
Fundamental Parameters ◽  
Detection Technology ◽  
Capacitive Method ◽  
Characteristic Values

The capacitive method is considered to be a suitable icing-detection technology, but the lack of fundamental parameters restricts the development of icing-detection sensors. In this paper, an artificial icing laboratory, a capacitive sensor, and some simulation conductors have been designed for obtaining the artificial icing samples. Subsequently, the same characteristic values of artificial icing have been measured by an LCR device, under a selected frequency. This research found that the value of the icing dielectric constant closely correlated with its density, internal sublayer, and the test temperature. Finally, a fitting formula has been presented for calculating the relative dielectric constant, which may provide some important reference value for the design of icing-detection sensors.

scholarly journals ANALISIS JUMLAH MUATAN LISTRIK SERTA ENERGI PADA KAPASITOR BERDASARKAN KONSTANTA DIELEKTRIK SUATU MATERIAL

2021 ◽  
Vol 7 (1) ◽  
pp. 176
Author(s):  
Sinta Marito Siagian ◽  
Gede Wiratma Jaya ◽  
Indah Nurhidayati
Keyword(s):  
Dielectric Constant ◽  
Quantitative Analysis ◽  
Electric Charge ◽  
Constant Voltage ◽  
Microsoft Excel ◽  
Energy Value ◽  
In Series

ABSTRAKPenelitian ini dilakukan untuk mengetahui nilai muatan listrik, nilai kapasitor yang dirangkai secara seri dan paralel kemudian nilai energi yang tersimpan pada kapasitor berdasarkan jenis-jenis material dengan konstanta dielektrik yang telah ditentukan. Metode yang dilakukan adalah mengkaji masing-masing nilai tersebut berdasarkan konstanta dielektrik dengan perhitungan matematis berbantuan Microsoft excel untuk menghasilkan grafiknya. Adapun tegangan yang digunakan pada metode ini adalah 20, 40, 60 dan 100 volt dan material yang dianalisis antara lain kaca, udara, mika, kertas dan polystiren. Analisis dilakukan menggunakan analisis kuantitatif yang memanfaatkan data berupa angka yang dipresentasikan melalui grafik. Ditemukan hasil perhitungan matematis bahwa kaca memiliki jumlah muatan yang lebih besar dibandingkan dengan material yang lainnya. pada saat dirangkaiakan secara seri dan paralel diperoleh bahwa jumlah muatan kapasitor yang dirangkaiakan secara paralel jauh lebih besar dibandingkan seri, energi yang tersimpan pada kapasitor yang dirangkaikan secara paralel juga memiliki nilai yang besar dari pada kapasitor yang dirangkai secara seri. Kata kunci: kapasitor; konstata dielektrik; tegangan. ABSTRACTThis research aims are to analyze the value of the electric charge, the value of the capacitor connected in series and paralel then the energy value stored in the capacitor based on the types of materials with determined a dielectric constant. The method used  to examine each of these values based on the dielectric constant with mathematical calculations assisted by Microsoft Excel to produce the graph. The voltages used on this methode are 20, 40, 60, and 100. The analysis using quantitative analysis that utilizes data in the form of numbers presented through graphs. It has been studied based on the physical formulation of the value of an electric charge against the dielectric constant of glass, air, mica, paper and polystyrene. It was found that the results of mathematical calculations show that glass has a greater amount of charge compared to other materials. When assembled in series and paralel, it is found that the amount of charge on the capacitor connected in paralel is much greater than in series, the energy stored in the capacitor connected in paralel also has a greater value than the capacitor connected in series. Keywords: capasitor; dielectric constant; voltage.

scholarly journals Análisis cristalográfico, morfológico, eléctrico, óptico y magnético del nuevo material Dy2BiFeO6

2018 ◽  
Vol 9 (1) ◽  
Author(s):  
Jairo Roa-Rojas
Keyword(s):  
Dielectric Constant ◽  
Energy Gap ◽  
Magnetic Hysteresis ◽  
Magnetic Ordering ◽  
Relative Dielectric Constant ◽  
Double Perovskite ◽  
Crystallographic Analysis ◽  
Weiss Temperature ◽  
Constant E ◽  
Diffraction Patterns

We report structural analysis, surface morphology, magnetic ordering, dielectric response, optical feature and the electronic structure of the Dy2BiFeO6 novel complex perovskite. The samples were produced by the standard solid-state reaction recipe. Crystallographic analysis was performed by Rietveld refinement of experimental X-ray diffraction patterns. Results show that this material crystallizes in a perovskite with orthorhombic structure, which corresponds to the Pnma (#62) space group. From the Curie-Weiss fitting on the curve of susceptibility as a function of temperature we establish that the ordering corresponds to a paramagnetic-antiferromagnetic transition, with a Weiss temperature q=-18,5 K, which is compatible with the behavior of the inverse of susceptibility as a function of temperature, and a Néel temperatura TN=50,8 K. The Curie constant allowed for us to obtain an effective magnetic moment of 15,7 mB. The result of magnetization as a function of the applied field, measured at T=50 K, shows a magnetic hysteresis behavior that corroborate the magnetic ordering present for this temperature value. Measurements of the dielectric constant as a function of applied frequencies at room temperature give as a result a high relative dielectric constant (e=780). The reflectance curve as a function of the wavelength reveals the typical behavior of a double perovskite-like material and permits to obtain the energy gap 2,74 eV, which is characteristic of a semiconductor material.

Kinetic Study of Portland Cement Hydration with Ground Penetrating Radar

2013 ◽  
Vol 539 ◽  
pp. 25-29
Author(s):  
Wei Chen ◽  
Pei Liang Shen ◽  
Jian Xin Lu ◽  
Wan Ru Zhang
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Ground Penetrating Radar ◽  
Cement Hydration ◽  
Relative Dielectric Constant ◽  
Gradual Decline ◽  
Hardening Process ◽  
Ground Penetrating ◽  
Kinetics Of ◽  
Portland Cement Hydration

The variations of dielectric constant and the amplitude of reflected EM wave of concrete during the first 3 days are measured with Ground Penetrating Radar (GPR) at 20 oC. The amplitude decreases sharply after mixing with water, and then increases till a stabilized stage, followed by a gradual decline. The relative dielectric constant decreases with increasing hydrating time. The results show that the dielectric properties of concrete can be used as an effective way of studying the kinetics of concrete setting and hardening process at early ages.

Modified Organic low-k Dielectric Layers on Fired LTCC Substrates

2012 ◽  
Vol 2012 (CICMT) ◽  
pp. 000394-000399
Author(s):  
Achim Bittner ◽  
Ulrich Schmid
Keyword(s):  
Dielectric Constant ◽  
Film Thickness ◽  
High Surface ◽  
Relative Dielectric Constant ◽  
Compound Layer ◽  
Substrate Material ◽  
Filler Material ◽  
Filler Concentration ◽  
Rotating Speed ◽  
S Parameter

In this study, the reduction of permittivity of LTCC substrates by coating with a polyimide compound containing hollow glass microspheres as filler material is described. By incorporating the filler material, the dielectric constant of the substrate material is locally lowered to improve the high-frequency performance of antennas operated in the GHz range. Furthermore, by adding the filler material to the liquid polyimide precursor the layer thickness is heightened from maximum 10 μm to above 80 μm which is enough to fill cavities in LTCC substrates. Two compound materials with filler to polymer ratios 1:7.5 and 1:10 are mixed. Afterwards they are deposited by spin coating onto LTCC substrates. The film thickness depends on the rotating speed and the filler content. With the higher filler concentration and low rotating speed of 500 rpm 82 μm thick polymer films can be achieved. The high surface roughness can be reduced afterwards by adding additional pure polyimide layers on top to Ra= 3 μm. The dielectric constant of the entire substrate consisting of the LTCC and the resulting compound material is measured using a ring resonator in microstrip configuration. From the resonances occurring in the transmission S-parameter |S21| spectrum between 1 to 10 GHz, the relative dielectric constant can be determined. Using 820 μm thick LTCC substrates a relatively low reduction from εr = 7.8 to 6.6 is achieved. However, due to permittivity can be reduced with higher microsphere amounts, the dielectric constant of pure polyimide of εr= 3.3 can also be reduced. Furthermore due to the sufficiently high film thickness of the modified substrates, the compound layer can be used as single dielectric layer.

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