Spectral theory of diffraction of electromagnetic waves by a strip in the plane interface of two semi-infinite media

1979 ◽  
Vol 57 (8) ◽  
pp. 1148-1156 ◽  
Author(s):  
J. M. van Splunter ◽  
P. M. van den Berg
Keyword(s):  
Fourier Transform ◽  
Electromagnetic Waves ◽  
Power Flow ◽  
Plane Electromagnetic Wave ◽  
Plane Waves ◽  
Surface Current ◽  
Iteration Scheme ◽  
Plane Interface ◽  
Flow Density ◽  
Infinite Media

The diffraction of a plane electromagnetic wave by a cylindrical strip in the plane interface of two semi-infinite media has been investigated. For both the case of E polarization and the case of H polarization, the scattered field is written as a continuous superposition of plane waves (spatial Fourier type of integral). The complex amplitudes of these waves are directly related to the spatial Fourier transform of the surface current on the strip. In order to determine the surface current, a relatively simple iteration scheme has been developed. At the numerical calculations we successfully take advantage of the presence of a Fast Fourier Transform procedure. Numerical results pertaining to the power flow density are presented at different locations and as a function of the width of the strip. Furthermore, the scattering cross section of the strip, as a function of the electromagnetic contrast of the different media, is calculated.

Diffraction of Electromagnetic Waves by a Semi-Infinite Screen in a Layered Medium

1975 ◽  
Vol 53 (14) ◽  
pp. 1305-1317 ◽  
Author(s):  
Wiebe G. Heitman ◽  
P. M. van den Berg
Keyword(s):  
Electromagnetic Wave ◽  
Electromagnetic Waves ◽  
Power Flow ◽  
Layered Medium ◽  
Plane Electromagnetic Wave ◽  
Flow Density ◽  
Two Dimensional ◽  
Electromagnetic Power

The diffraction of a plane electromagnetic wave by a semi-infinite screen in one of the plane interfaces of a layered medium is investigated theoretically. The screen of vanishing thickness is assumed to be electrically perfectly conducting. Two separate two dimensional scalar problems are dealt with, viz. the case of E polarization and H polarization. The resulting unknown field functions are determined with the aid of the Wiener–Hopf technique. Subsequently, the electromagnetic power flow density is calculated at different locations and as a function of the electromagnetic contrast of the different media.

Electromagnetic waves

2018 ◽  
Author(s):  
Nathalie Deruelle ◽  
Jean-Philippe Uzan
Keyword(s):  
Plane Wave ◽  
Electromagnetic Waves ◽  
Maxwell Equations ◽  
Plane Waves ◽  
Geometrical Optics ◽  
Particle Detection ◽  
Spatial Coordinates ◽  
A Charge

This chapter examines solutions to the Maxwell equations in a vacuum: monochromatic plane waves and their polarizations, plane waves, and the motion of a charge in the field of a wave (which is the principle upon which particle detection is based). A plane wave is a solution of the vacuum Maxwell equations which depends on only one of the Cartesian spatial coordinates. The monochromatic plane waves form a basis (in the sense of distributions, because they are not square-integrable) in which any solution of the vacuum Maxwell equations can be expanded. The chapter concludes by giving the conditions for the geometrical optics limit. It also establishes the connection between electromagnetic waves and the kinematic description of light discussed in Book 1.

scholarly journals Hypersensitized Metamaterials Based on a Corona-Shaped Resonator for Efficient Detection of Glucose

2020 ◽  
Vol 11 (1) ◽  
pp. 103
Author(s):  
Yadgar I. Abdulkarim ◽  
Fahmi F. Muhammadsharif ◽  
Mehmet Bakır ◽  
Halgurd N. Awl ◽  
Muharrem Karaaslan ◽  
...  
Keyword(s):  
Resonance Frequency ◽  
Glucose Concentration ◽  
Electromagnetic Waves ◽  
Surface Current ◽  
Superior Performance ◽  
Promising Candidate ◽  
Efficient Detection ◽  
Circular Structure ◽  
Clear Shift ◽  
Current Electric Field

In this work, a new design for a real-time noninvasive metamaterial sensor, based on a corona-shaped resonator, is proposed. The sensor was designed numerically and fabricated experimentally in order to be utilized for efficient detection of glucose in aqueous solutions such as water and blood. The sensor was inspired by a corona in-plane-shaped design with the presumption that its circular structure might produce a broader interaction of the electromagnetic waves with the glucose samples. A clear shift in the resonance frequency was observed for various glucose samples, which implies that the proposed sensor has a good sensitivity and can be easily utilized to distinguish any glucose concentration, even though their dielectric coefficients are close. Results showed a superior performance in terms of resonance frequency shift (1.51 GHz) and quality factor (246) compared to those reported in the literature. The transmission variation level ∆|S21| was investigated for glucose concentration in both water and blood. The sensing mechanism was elaborated through the surface current, electric field and magnetic field distributions on the corona resonator. The proposed metamaterials sensor is considered to be a promising candidate for biosensor and medicine applications in human glycaemia monitoring.

Structure-Borne Power Transmission in Thin Naturally Orthotropic Plates: General Case

2003 ◽  
Vol 9 (10) ◽  
pp. 1189-1199 ◽  
Author(s):  
Nirmal Kumar Mandal ◽  
Roslan Abd. Rahman ◽  
M. Salman Leong
Keyword(s):  
Fourier Transform ◽  
Power Flow ◽  
Power Transmission ◽  
Far Field ◽  
Orthotropic Plates ◽  
Flow Estimation ◽  
Structural Intensity ◽  
Vibration Power Flow ◽  
Conventional Idea ◽  
Bending Wave

The structural intensity technique is usually used to estimate vibration power flow in structures. This method is used to determine vibration power flow in thin naturally orthotropic plates. The bending wave is considered to find general vibration power transmission in the frequency domain that is not approximated by far field conditions. This intensity formulation defines power flow per unit width of the plates (W m−1) similar to that of the conventional idea. Power flow estimation is formulated using cross-spectra of field signals, facilitating the use of a fast Fourier transform analyzer.

CHANGE OF THE FRESH MUSHROOM TEXTURE IN THE PROCESS OF REFRIGERATED STORAGE AFTER PROCESSING WITH UV RADIATION

2020 ◽  
Author(s):  
В.В. Кондратенко ◽  
Н.И. Федянина ◽  
О.В. Карастоянова
Keyword(s):  
Ultraviolet Radiation ◽  
Agaricus Bisporus ◽  
Power Flow ◽  
Storage Capacity ◽  
Dose Range ◽  
Short Wave ◽  
Flow Density ◽  
Fruiting Bodies ◽  
Negative Effect ◽  
Wave Range

Исследовано влияние обработки свежих плодовых тел шампиньонов (Agaricus bisporus) ультрафиолетовым излучением в коротковолновом диапазоне С (100–280 нм) дозами 160, 320, 480, 640, 800 Дж/м2 при плотности потока мощности 2,7 · 103Дж/с · м2 на изменение качественного показателя хранимоспособности – текстуры грибов в процессе холодильного хранения. Хранение упаковок с грибами осуществляли в холодильной камере при t 4–5°С и относительной влажности воздуха 85–90%. Контроль изменения показателя хранимоспособности проводили по истечении 1, 3, 8, 13, 16, 21, 24 и 27-ми сут. В процессе хранения исследовали динамику изменения текстуры грибов, кг/см2. Установлено, что обработка в диапазоне доз до 418 Дж/м2 приводит к негативному эффекту изменения хранимоспособности и является нецелесообразной. Определено, что обработка УФ излучением в диапазоне доз 418–800 Дж/м2 приводит к увеличению хранимоспособности и достигает своего экстремума при 685 Дж/м2. При экстраполяции результатов экспериментальных данных такая тенденция отмечается, предположительно, до дозы 876 Дж/м2. Получены динамики текстуры в процессе хранения после обработки УФ излучением. Разработано математическое описание зависимости предельной хранимоспособности по показателю текстуры грибов от дозы облучения. The effect of irradiation of fresh the fruiting bodies of champignons (Agaricus bisporus) with ultraviolet radiation in the short – wave range C (100–280 nm) doses of 160, 320, 480, 640, 800 J/m2at a power flow density of 2,7 · 103 J/s · m2 on the change in the quality indicator of ability to store – the texture of mushrooms during cold storage was studied. Packages with mushrooms were stored in a refrigerator at t 4–5°C and relative humidity 85–90%. Monitoring of changes of ability to store was carried after 1, 3, 8, 13, 16, 21, 24 and 27 days. During storage, studied the dynamics of changes in the texture of mushrooms, kg/cm2. It was found that irradiation in the dose range up to 418 J/m2 leads to a negative effect of changes of ability to store and is impractical. It was determined that ultraviolet radiation in the dose range of 418– 800 J/m2leads to an increase of ability to store and reaches extreme at 685 J/m2. When extrapolating the results of experimental data, such a tendency is presumably observed up to a dose of 876 J/m2. The dynamics of the texture obtained during storage after processing with ultraviolet radiation. A mathematical description of the dependence of the maximum storage capacity in terms of the texture of mushrooms on the radiation dose is developed.

scholarly journals Two basic systems of maxwell’s equations in a rotating frame: application in theory of ring laser gyro

2020 ◽  
pp. 64-73
Author(s):  
Evgen Bondarenko
Keyword(s):  
Ring Laser ◽  
Electromagnetic Waves ◽  
Maxwell’S Equations ◽  
Maxwell's Equations ◽  
Plane Waves ◽  
Rotating Frame ◽  
Cylindrical Coordinates ◽  
Laser Gyro ◽  
Component Form ◽  
Velocity Approximation

In the paper, using a linear in angular velocity approximation, two basic well-known systems of Maxwell’s equations in a uniformly rotating frame of reference are considered. The first system of equations was first obtained in the work [L. I. Schiff, Proc. Natl. Acad. Sci. USA 25, 391 (1939)] on the base of use of the formalism of the theory of general relativity, and the second one – in the work [W. M. Irvine, Physica 30, 1160 (1964)] on the base of use of the method of orthonormal tetrad in this theory. In the paper, in the approximation of plane waves, these two vectorial systems of Maxwell’s equations are simplified and rewritten in cylindrical coordinates in scalar component form in order to find the lows of propagation of transversal components of electromagnetic waves in a circular resonator of ring laser gyro in the case of its rotation about sensitivity axis. On the base of these two simplified systems of Maxwell’s equations, the well-known wave equation and its analytical solutions for the named transversal components are obtained. As a result of substitution of these solutions into the first and second simplified systems of Maxwell’s equations, it is revealed that they satisfy only the second one.  On this basis, the conclusion is made that the second system of Maxwell’s equations is more suitable for application in the theory of ring laser gyro than the first one.

scholarly journals The relativity theory of plane waves

1926 ◽  
Vol 111 (757) ◽  
pp. 95-104 ◽  
Keyword(s):  
Gravitational Field ◽  
Electromagnetic Waves ◽  
Small Amplitude ◽  
Plane Waves ◽  
Cumulative Effect ◽  
Relativity Theory ◽  
Transverse Waves ◽  
Propagation Of Light ◽  
Cumulative Change ◽  
The Waves

Weyl has shown that any gravitational wave of small amplitude may be regarded as the result of the superposition of waves of three types, viz.: (i) longitudinal-longitudinal; (ii) longitudinal-transverse; (iii) transverse-transverse. Eddington carried the matter much further by showing that waves of the first two types are spurious; they are “merely sinuosities in the co­ordinate system,” and they disappear on the adoption of an appropriate co-ordinate system. The only physically significant waves are transverse-transverse waves, and these are propagated with the velocity of light. He further considers electromagnetic waves and identifies light with a particular type of transverse-transverse wave. There is, however, a difficulty about the solution as left by Eddington. In its gravitational aspect light is not periodic. The gravitational potentials contain, in addition to periodic terms, an aperiodic term which increases without limit and which seems to indicate that light cannot be propagated indefinitely either in space or time. This is, of course, explained by noting that the propagation of light implies a transfer of energy, and that the consequent change in the distribution of energy will be reflected in a cumulative change in the gravitational field. But, if light cannot be propagated indefinitely, the fact itself is important, whatever be its explana­tion, for the propagation of light over very great distances is one of the primary facts which the relativity theory or any like theory must meet. In endeavouring to throw further light on this question, it seemed desirable to avoid the assumption that the amplitudes of the waves are small; terms neglected on this ground might well have a cumulative effect. All the solu­tions discussed in this paper are exact.

scholarly journals Design and experimental analysis of dual-band polarization converting metasurface for microwave applications

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Bilawal Khan ◽  
Babar Kamal ◽  
Sadiq Ullah ◽  
Imran Khan ◽  
Jawad Ali Shah ◽  
...  
Keyword(s):  
Electromagnetic Waves ◽  
Polarization State ◽  
Plane Waves ◽  
Microwave Frequency ◽  
Dual Band ◽  
Orthogonal Polarization ◽  
Frequency Bands ◽  
Practical Applications ◽  
Sensor Applications ◽  
Polarized Waves

Abstract The manipulation of polarization state of electromagnetic waves is of great importance in many practical applications. In this paper, the reflection characteristics of a thin and dual-band metasurface are examined in the microwave frequency regime. The metasurface consists of a 22 × 22 element array of periodic unit cells. The geometry of the unit cell consists of three layers, including a 45° inclined dipole shape metal patch on top, which is backed by a 1.6 mm thick FR-4 substrate in the middle, and a fully reflective metallic mirror at the bottom. The proposed surface is exposed to horizontally (x) or vertically (y) polarized plane waves and the co and cross polarization reflection coefficients of the reflected waves are investigated experimentally in the 6–26 GHz frequency range. The metasurface is designed to convert incident waves of known polarization state (horizontal or vertical) to orthogonal polarization state (vertical and horizontal) in two distinct frequency bands, i.e. 7.1–8 GHz and 13.3–25.8 GHz. In these two frequency bands the simulated and experimental results are in good agreement. The polarization conversion ratio (PCR) of the surface is greater than 95% in the targeted frequency bands. A detailed parametric analysis of the metasurface is also discussed in this work and it has been estimated that the surface has the additional ability to convert linearly polarized waves to circularly polarized waves at several distinct frequencies. The proposed metasurface can be utilized in sensor applications, stealth technology, electromagnetic measurements, and antennas design.

A semianalytical solution for the propagation of electromagnetic waves in 3‐D lossy orthotropic media

Geophysics ◽  
2001 ◽  
Vol 66 (4) ◽  
pp. 1141-1148 ◽  
Author(s):  
José M. Carcione ◽  
Fabio Cavallini
Keyword(s):  
Magnetic Field ◽  
Plane Wave ◽  
Electromagnetic Waves ◽  
Plane Waves ◽  
Computer Experiment ◽  
Transverse Magnetic ◽  
Wave Analysis ◽  
Helmholtz Equations ◽  
Magnetic Surfaces ◽  
Time Histories

We derive an analytical solution for electromagnetic waves propagating in a 3‐D lossy orthotropic medium for which the electric permittivity tensor is proportional to the magnetic permeability tensor. The solution is obtained through a change of coordinates that transforms the spatial differential operator into a pure Laplace operator and the differential equations for the electric and magnetic field components into pure Helmholtz equations. A plane‐wave analysis gives the expression of the slowness and attenuation surfaces as a function of frequency and propagation direction. The transverse electric and transverse magnetic surfaces degenerate to one repeated sheet so that, in any direction, the two differently polarized plane waves have the same slowness. A computer experiment with realistic geophysical parameters has shown that the anisotropic propagation and dissipation properties emerging from plane‐wave analysis agree with the different time histories of the magnetic field computed at a number of representative receiver locations.

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