Kharkov National University
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1.  Multifunctional measuring platform for investigations parameters of metal-dielectric structures
V.A. Katrich, D.V. Mayboroda, S.A. Pogarsky, I.I. Saprykin
Automation complex, dielectric image guide, energetic characteristics
Vestnik KhNU 712 Pages. 21-24

The multifunctional automation measuring platform for ultra high frequencies parameters definition has been de- signed. The basis of this complex is the controlled mechanical platform which allows to measure the field amplitudes along two orthogonal coordinates. The processing of measuring date realizes with the help of special software. The measuring of energetic characteristics of radiating module based on dielectric image guide has been carried out



2.  Radiation of electromagnetic waves by the system of transverse and longitudinal slots in the wide wall of rectangular waveguide
S.L. Berdnik
Antenna array, multi-frequency antenna, slot system, multimode rectangular waveguide
Vestnik KhNU 712 Pages. 25-29

The problem of radiation of electromagnetic waves by the double-frequency multielement slot array on a multimode waveguide was solved by the Galerkin's method. The radiating aperture is two systems of longitudinal and transverse slots in the wide wall of the rectangular waveguide. The power and directional characteristics of such structure were investigated. Thickness of the waveguide wall, interior and exterior interactions between slots were taken into account at calculations



3.  Longitudinal slot radiators cut in circular waveguide
E.Y. Belogurov, V.A. Katrich, V.A. Lyaschenko
circular waveguide, Axial slot, electromagnetic waves, radiation, slot antennas
Vestnik KhNU 712 Pages. 37-41

Using method of magnetomotive forces investigations of behaviors of longitudinal slots that were cut in wall of the circular waveguide were carried out. Expressions of internal self-admittance and transfer conductance were de- rived. The possibility of creation of a tapered illumination that forms radiation pattern with low side lobes on long slot cut in circular waveguide was shown



4.  Electromagnetic wave detraction on a resistive unclosed cone
V.A. Doroshenko, O.G. Litvinova
diffraction, resistive, longitudinal slots, An integral transform, Analytical solutions
Vestnik KhNU 712 Pages. 95-99

Problem of harmonic electromagnetic wave diffraction on a resistive cone with longitudinal slots is considered. The boundary problem solution uses the Kontorovich-Lebedev integral transform and a semi-inversion method. Analytical solutions are obtained for the cone with a lot of narrow slots and reactive impedance. Impedance and longitudinal slots effects on scattering field structure is studied



5.  Same question of modeling of tunnel contact semiconductor structure
O.V. Botsula, E.D. Prokhorov
tunnel cathode, negative differential conductivity, contacts, current - voltage characteristics, cathode, Anode
Vestnik KhNU 712 Pages. 119-122

Electronic processes are considered at course of a current through semi-conductor structure with the tunnel cathode. The approach to modelling the structures including as a component tunnel geterojunction is offered. Static characteristics of structures to a basis geterojunction GaAs/AIGaAs received with application of the offered technique are resulted



6.  Stimulation of the size evolution of the gas includes in a liquid by electromagnetic waves
B.G. Yemets
electromagnetic waves, Air bubbles in liquid, temperature field, convection
Vestnik KhNU 712 Pages. 127-131

Based on the model considerations it was shown that irradiation of liquids containing gas inclusions with electromagnetic fields of "slowly-convective" intensity is conducive to the changes in the inclusion size



7.  On the field fluctuations in the diffraction pattern of focusing systems
Ya.S. Shifrin
fluctuations, Amplitude, phase, focal plane
Vestnik KhNU 756 Pages. 5-10

There are considered the amplitude and phase fluctuations of the field in the focal plane of the focusing system, when a was with the field fluctuations falls on it. Plots illustrating the distribution of dispersions of amplitude and phase of the field along coordinate axes in the focal plane are given. There are analyzed a general case when both the amplitude and phase fluctuation of the field are present in the incident wave, as well as cases when it is possible to be restricted by regard of only either the phase or the amplitude fluctuations of the field in the antenna aperture. It is shown that in the latter cases, for determination of dispersions of the phase and amplitude fluctuation of die field in the focal plane, it is possible to use the same pictures with tk corresponding replacement of curves and conclusions accompanying them.



8.  Radioacoustic wind sounding of the atmosphere bo un dat y layer: history of the development and perspectives
Y. N. Ulyanov, V. I. Vetrov, N. G. Maksimova
radioacoustic, wind, sounding, Atmosphere, boundary layer, profile, Adaptation
Vestnik KhNU 756 Pages. 27-32

The article is devoted to the potentialities of the method of radioacoustic sounding when monitoring the vertical structure of the wind in the atmosphere boundary layer (ABL). A review of methods for radioacoustic measurements of the horizontal wind velocity and direction is based on the developments of the authors and their experience in this field as well as on the world experience. It is emphasized that the radioacoustic method for sounding the wind in ABL is perspective, since for the RAS equipment, there are not characteristic neither high levels of the electromagnetic pollution of the environment like for radiolocation wind profilers - radars nor loss of the serviceability at ligh levels of the ambient acoustic noise like for acoustic wind profilers - sodars.



9.  ELECTROMAGNETIC WAVE SCATTERING FROM ANISOTROPIC INCLUSION IN RECTANGULAR SHORT-CIRCUIT WAVEGUIDE
N.P. Zhuck, V.I. Fesenko, S.N. Shulga, O.V. Bagatskaya, He Shi
scattering matrix, rectangular waveguide, Anisotropic medium
Vestnik KhNU 756 Pages. 33-37

The problem of determination of the scattering matrix coefficients from anisotropic inclusion in one side short-circuit waveguide was considered. Calculation of the scattering matrix coefficient |S10| for the anisotropic slab in the end of the empty rectangular waveguide is presented



10.  EXCITATION OF AN UNCLOSED CONE PLACED AT AN IMPEDANCE PLANE
V.A. Doroshenko, O.G. Litvinova, A.V. Sova
excitation, An impedance plane, cone, longitudinal slots, Analytical solutions
Vestnik KhNU 756 Pages. 42-46

By using the approach that is based on applying the Kontorovich-lebedev integral transforms method and a semi-inversion method an excitation boundary problem for a cone with periodical longitudinal slots provided that cone placed at an impedance plane is investigated. It is showed that the problem under consideration is equivalent to solving a system of linear algebraic equations for Fourier coefficients of electromagnetic field components. Analytical solutions are obtained for a semi- transparent cone and special plane impedance. Impedance plane effects are studied



11.  INFLUENCE of ENVIRONMENT ON the FIELD, SCATTERING ON the LATTICE WITH LAYER, AT ANY FALL of the WAVE
A.I. Adonina, V.B. Khokh
lattice, environment, dielectric, A stream of capacity, method of Riman-Hilbert problem
Vestnik KhNU 756 Pages. 51-56

The decision of a task in view is carried out for and the fields appropriate to two subsystems on which the system of the equations of the Maxwell for environments is divided. Integrated characteristics of a field are determined from the decision of systems of the linear algebraic equations received by a method of method of Riman-Hilbert problem , for a case when the smallest parameter decreases in inverse proportion to a square n->infinity. Programs (fort) with construction of diagrams are made. The analysis of the diagrams in part given in work, allows to establish influence of parameters of structure and corners of fall of a wave on anomalies in an absent-minded field for each concrete case



12.  The analytical method for a periodical sequence of the alternate grates of dielectric bars investigate
V.B. Kazanskiy
thick grate of dielectric bars, Anisotropic layer, periodic structure, propagation constant, scattering coefficients
Vestnik KhNU 756 Pages. 79-82

The electromagnetic properties of a finite periodic sequence of the thick grates of dielectric bars are investigated. The grates are identified with the homogeneous anisotropic layer of an appropriate thickness, in order to generalize, the layers which anisotropic properties of both permittivity and permeability are employed. The sequence scattering .coefficients are determined in analytical form using the circuit theory and the matrix functions techniques. Physical analysis of the frequency, angle and interference dependencies of the scattered field amplitude is carried out.



13.  The Gaussian beam scattering on the bounded sequence of alternate grates of dielectric bars
V.B. Kazanskiy, V.R. Tuz, D.V. Yudintsev
Gaussian beam, thick grate of dielectric bars, Anisotropic layer, periodic structure
Vestnik KhNU 756 Pages. 83-86

The Gaussian beam scattering on bounded periodical sequence of thick grates of dielectric bars are investigated. Identification of discrete structure with appropriate thickness homogeneous anisotropic layer was carried out for define sequence basic element transmission matrix. The sequence scattering coefficients were written down via Mougin polynomials. The effects of form distortion, beam splitting into several beams, side shift of beam axe were shown. Their correlation with scattering coefficients phase and module angle dependence of separate grates was established.



14.  GAUSSIAN EXPANSIONS FOR RADIATION PATTERN OF AN OPEN-ENDED LINE WITH IMPEDANCE BORDERS
A.P. Udovenko
Aperture distribution, impedance border, orthogonal functions, diffraction integral, feed
Vestnik KhNU 756 Pages. 87-90

Near-field and far-field two-parameter expansions in terms of Laguerre-Gaussian orthogonal basis functions are proposed, which take into account the effect of impedance feed borders. The expansions enable the feed characteristics on a base of lines with impedance borders to be calculated in wide frequency region. Radiation intensity distributions for the open-ended two-layer metal-shielded dielectric waveguide in a nonresonance regions of surface impedance varying, relative errors of expansion truncations, comparison with experimental data are presented



15.  SPECKLE INTERFEROMETRICIAN METHOD FOR ANEMOMETRICIAN OF TURBULENT STREAMS
G.N. Dolya, .N. Katunin, .V. Sadovy, S.I. Shmatkov
, speckle interferometrician, Anemometrician, speckle painting, light-reflecting coverage
Vestnik KhNU 756 Pages. 118-122

In this paper is researched the possibility of the use of the modified speckle interferometrician method for anemometrician of turbulent streams. It is developed laser anemometer on the basis of the modified speckle interferometrician method at the applications of light-reflecting coverage. Is dependence of increase of border frequency of signals spectrum at growth of speed of stream transversal to the ray. Dependence of spectrum of fluctuations the adopted signal on the degree of the brought distortions in at a different temperature of turbulent stream is explored



16.  SELECTIVE excitation of the HIGH-order MODES IN THE waveguide quasioptical RESONATOR
A.V. Volodenko, O.V. Gurin, A.V. Degtyarev, V.A. Maslov, V.A. Svich, A.N. Topkov
waveguide quasioptical resonator, excitation of the high-order transverse modes, An amplitude filter, Fourier optics
Vestnik KhNU 756 Pages. 123-131

The method of the space Fourier-filtration for selective excitation of separated high-order transverse modes in the waveguide quasioptical resonator with a high discrimination degree of undesirable modes is proposed and realized. It is carried out numerical study of characteristics of some the lowest on loss transverse modes of the dielectric and metal resonators of the submillimeter laser from geometric sizes of reflectors and parameters of the space filter on the nonuniform mirror. Configurations of the amplitude-stepped mirrors for shaping the high-order transverse modes in the laser resonators containing waveguides and open parts are proposed



17.  CALCULATION and EXPERIMENTAL MEASUREMENT OF ANODE BLOCKS PARAMETERS OF MAGNETRONS
K.M. Basrawi, G.I. Churyumov
magnetron, Anode block, Q quality factor, loaded Q factor, equivalent capacity, mode
Vestnik KhNU 756 Pages. 132-138

In this paper the outcomes of calculation and experimental measurements of cold parameters of the pulse and continuous X - range magnetrons are presented. The measuring and calculation techniques of equivalent capacities of the anode blocks of the magnetrons as well as Q quality factor, loaded Q factor and external Q factors of the resonant system for main N/2 - mode and nearest N/2 -1 and N/2 -2 -modes is given



18.  On the primary mechanism for microwave therapeutic effects arising during gamma ray pathology
B. G. Yemets
electromagnetic microwaves, gamma rays, Air bubbles, biologically active points
Vestnik KhNU 756 Pages. 139-143

The biologically active points (BAP) show an increase in size due to an increase in size of air bubbles at near-membrane water layer in the biologically active point cells. The increase in the air bubble size is produced by sweeping the microwave frequency.



19.  Directed and polarization characteristics of the aperture of the circular waveguide with impedance flange
N.N. Gorobets, V.M. Dakhov, I.V. Gorbach
microwave, Antennas, waveguides, polarization, pattern
Vestnik KhNU 806 Pages. 3-7

The amplitude and polarization patterns of the radiator in the form of the aperture of circular waveguide with impedance flange, excited by the dominant wave, have been measured by the method of the indicator antenna with polarization plane rotation. It is shown that such radiators have an axial-symmetric pattern, a wide polarization pattern and a low level of side lobes.


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20.  Features of the forest radio emissi
L.M. Atroshenko, K.P. Gaikovich, N.N. Gorobets, V.N. Gorobets
radio emission, A forest
Vestnik KhNU 806 Pages. 8-13

Dielectric permeability of sheet plates of deciduous breeds of trees, dependence of the level of own wood signal from its projective covering, temperature distinctions, diffraction of radiowaves and their plural reflections in a crone of trees are investigated.


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21.  Arbitrary falling of wave on grate with by nisotropic layer
A.I.Adonina, R.R.Naumov, A.I.Sljusarev
grate, magnetodielectric, stream of power, method of Riman-Gilbert, Anisotropic, resonator
Vestnik KhNU 806 Pages. 22-28

A decision set the problem is conducted for and pour, proper two subsystems into which the system of equalizations of Maxwell is divided for anisotropic environments. The mixed field (in the case of the arbitrary falling of wave) is determined as a sum of two types pour. Integral descriptions are from the decision of the reduced endless systems of linear algebraic equalizations, got the method of task of Riman-Gilbert. The analysis of the graphs, partly resulted in work, allows to set influencing of parameters of structure and angles of incidence of wave on an anomaly in the dissipated field for every concrete case, and also to suppose and to confirm physical reasons of existence of anomalies a numeral account, as resonances of own waves in the opened resonator which is design the explored structure.


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22.  Way of transformation of the patterns of reception antennas
A.A. Sorokin, A.F Sorokin, O.V. Sokolova, R.N. Zaluzhniy, N.N. Gorobets
mirowaves, Antennas, pattern, Frenel zones
Vestnik KhNU 806 Pages. 29-32

the expedient of management by the shape of directional diagrams with the help of a fragmentation of Frenel zones is offered. Measuring the shape of a pattern diagram of the horn and spiral antennas are carried out. Peak allocations a builder of a field in short-range, medial and long-range bands for different frequency range are received and analyzed. By results of experiments intensity, a corner, radius for long-range and short-range bands is constructed 3D images.


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23.  Resonance phenomena occurring as a thin refractive cylinder diffracts the hertzian wave
Yu. I. Grebenyuk, N. G. Kokodiy, Khe Shi
diffraction, thin cylinder, refractive index, scattering, Absorption, weakening, resonance
Vestnik KhNU 806 Pages. 33-39

On the basis of solutions to the wave equation, the efficiency of dispersing, absorbing, and weakening the electromagnetic field that a thin cylinder with a large refractive index diffracts has been estimated. The transverse and longitudinal distribution of the electromagnetic field inside and outside of the cylinder has been calculated. The resonance is found to increase the intensity of both the electromagnetic wave field inside the cylinder and the scattered wave outside. Inside the cylinder at resonance, a wave propagating along its surface arises, and under some conditions, a wave propagating through the cylinder is also generated. As the refractive index is increased, the wave tracks the cylinder surface more closely, and its intensity is progressively enhanced.


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24.  The influence of a dispersion and losses to the interaction of impulse signal with the model of the biological tissues
O.N. Zheryobkina, O.V. Kazanskiy
impulse signal, A biological tissue, time domain, flatlayer dielectric, dispersion
Vestnik KhNU 806 Pages. 40-43

In this paper the interaction of the impulse signal with biological tissues on an example of the flatlayer dielectric that models consecutive layers a skin, fat, muscle tissue is investigated. In this model, it is taken into account dispersion of the dielectric permeability and losses in a medium. The calculation program is received in result. It accounts the space-time characteristics of the reflected and past signals for layers of the flatlayer dielectric with parameters of biological tissues. Influence of values of the dielectric permeability and angle of incidence on the characteristics of past and scattered signals also is considered.


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25.  Selection of the high-order modes in the waveguide resonator by means a phase-shifting mirror
A.V. Volodenko, O.V. Gurin, A.V. Degtyarev, V.A. Maslov, V.A. Svich, A.N. Topkov
waveguide quasioptical resonator, excitation of the high-order transverse modes, A phase filter, Fourier optics, selection
Vestnik KhNU 806 Pages. 87-91

The method of the space Fourier-filtration for selective excitation of separated high-order modes in the metal waveguide quasioptical resonator with a high discrimination degree of undesirable modes is realized. It is carried out numerical study of characteristics of some the lowest on loss transverse modes for the metal resonators of the submillimeter laser from resonator geometric sizes and parameters of the phase filter on the nonuniform mirror. Configurations of the phase-shifting mirrors for shaping of the high-order transverse modes in the laser resonators containing waveguides and open parts are proposed


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26.  Increase of free volume 0f the aip abundant in the water by the millimeter waves of low intensity
B. G. Yemets
electromagnetic waves, Air bubbles, field of temperature, convection
Vestnik KhNU 806 Pages. 103-106

Using an NMR technique the volume growth of the free ("bubble") air contained in water caused by low-intense electromagnetic waves is obtained. This change is caused by rectified diffusion of the dissolved air mass into bubbles. The increase in the free air may occure only under those conditions when there is no convection in the liquid, i. e. in the case of irradiating by means of low-intense waves.


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27.  The exitation Hp0 -waveguide wave of the Tbrunching with matching resonator
V. N. Mizernik, A. A. Shmat'ko
A branching of the waveguides, matching nouniformity, connection area, system of the linear algebraic equations
Vestnik KhNU 834 Pages. 8-12

In strong electrodynamics statement the problem of excitation Hp0 waveguide a wave by of the T-branching with two types matching resonator is solved: other-world and through passage. Results of calculation of amplitude-frequency characteristics of the module of factor of reflection for various parities between length of a wave and the geometrical sizes of structure are presented. Areas of value of parameters of the full coordination of wave guides are certain


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28.  Radiolocation complex for extra-atmospheric researches
A.F. Sorokin, A.A. Sorokin, N.N. Gorobets, O.V. Sokolova
radar, A, microwaves, space garbage
Vestnik KhNU 834 Pages. 25-30

The creation pulse radar is offered on the basis of radio engineering systems of the National centre of management and test of space means of Ukraine for the forecast asteroid of danger, cataloguing of space garbage, research of a solar crown, near a sun and interplanetary plasma, and also for radioastronomical researches of distant space. Is shown, that at use of large-sized aerials to a ADU - 1000 and P-400 such radar at length of a wave ~ 30 cm at heights ~ 105 finds out objects with the minimal sizes ~ 0,7 cm. On a disk of the Sun the spatial sanction ~ 103 kms


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29.  Earth profile plotting using pulse radar with scanning antenna array
A. S. Kutsenko, . V. Kazansky, N. N. Kolchigin
pulse radar, Antenna array, radar image
Vestnik KhNU 834 Pages. 37-41

This paper is devoted to development of radar signal processing technique which allows one to reconstruct earth profile and reveal and identify manmadc objects which arc situated on underlaying surface. The technique of signal processing and image construction is based on measuring of directional characteristics of the scene being investigated. Modeling of radar activity has been performed; radar images of some simple scatterers have been obtained. Possibility of using the technique for scene profile reconstruction and revealing of manmade objects situated on it has been shown


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30.  Structure and the contents of the hypertext databaseof problems of remote sounding of the ground from space
L.M.Atroshenko, N.N.Gorobets, L.P.Safronova, S.A.Smirnov
roblems of remote sensing, A database
Vestnik KhNU 834 Pages. 42-51

The principle of construction and filling of a hypertext database of problems of remote sensing of the Earth from Space including more 4000 problems RSE are described. The approach to an optimum choice of a sensor control is illustrated by the examples of use of active and passive sounding in a radiorange


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31.  Far-field distance of waveguide radiators
N.N. Gorobets, E.E. Ovsyannikova, A.V. Shishkova
rectangular waveguide, microwaves, boundary of far zone, Amplitude, phase radiation characteristics
Vestnik KhNU 834 Pages. 68-76

On the basis of Hertz potentials in Kirchhoff approximation the amplitude and phase radiation characteristics of open-ended rectangular waveguide excited by TE10 dominant mode are investigated at arbitrary distance from radiating aperture. The estimation criteria of far zone boundary for small (in comparison with the wavelength) waveguide radiators are presented. For such small radiators, the classic formula for calculation of far-field distance cannot be applied. Under suggested criteria the investigation of radiation characteristics are carried out. For waveguides with the sizes less then the wavelength in the waveguide, the boundaries of far-field distance are defined


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32.  Directivity characteristics of rarefied antenna arrays
N.N. Gorobets, A.A. Bulgakova
electromagnetic waves, Antennas, Antenna array, directivity characteristics
Vestnik KhNU 834 Pages. 89-94

The radiation pattern, directive gain and scattering coefficient of equivedistance linear array were calculated and their dependencies on the number of radiators and distances between them were analyzed. It is shown that for every number of radiators the optimal antenna length of L≈0,9(N-1), allowing to obtain the maximum of directive gain, occurs. For greater antenna length or increase in operating frequency, directive gain varies according to oscillating dependencies. The greater number of radiators occurs, the greater difference of maximums and minimums occurs. For small number of radiators (N≤8), the directivity characteristics of the array is higher, then for continuous antennas of the same electrical length. For N≥16, their characteristics coincide


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33.  Pulse water insonification for laboratory research of electromagnetic wave propagation and dispersion in randomly inhomogeneous media in order to meet the conditions close to working ones
V.B. Yuferov, A.N. Ponomarev, E.V. Mufel, A.N. Ozerov, I.V. Buravilov, V.N. Ishenko
electromagnetic wave propagation, inhomogeneous medium, Air bubbles in liquid, Acoustic pulse pneumatic radiator
Vestnik KhNU 834 Pages. 114-119

The efficiency of pulse water insonification by pneumatic radiator is shown. Such radiator enables the formation above the water surface of hydrometcors and aerosols with a desired concentration. It is necessary for laboratory research of fluctuation phenomena of the electromagnetic wave propagation in randomly inhomogeneous media. The use of pneumatic radiator makes possible lo remove salt from the solution. This enables a certain degree of control over liquid permittivity


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34.  Oscillation efficiency of TED diodes on the basis of nitrides
E. D. Prokhorov, O. V. Botsula, A. N. Zabazhan
AlN, GaN, InN-diodes, drift speed, oscillation efficiency
Vestnik KhNU 853 Pages. 15-21

Oscillation efficiency of intervalley transfer electrons diodes on the basis of nitrides (InN, GaN, AlN) is considered. Electric fields at peak oscillation efficiency are determined. The results have been compared to results for GaAs. The account of floatable potential in connections InGaN improves their power characteristics in comparison with power characteristics of these connections without taking into account floatable potential, maximal efficiency In0.8 Ga 0.2N and In0.5Ga0.5N diodes to compare to InN diodes on 30 % is higher (22 % to compare to 16,43 %) but at more high tensions of an electric field. The maximal oscillation efficiency is observed at higher electric fields than GaAs ( from 250 V/sm for InN to 1000 kV/sm for AlN)



35.  Inner partial mutual admittance of two overlopping longitudinal slots in a rectangular waveguide with dielectric layer parallel to narrow walls
A.A.Lyakhovsky, L.P.Yatsuk, A.F.Lyakhovsky
, layer, dielectric, slot, Admittance, scattering parameters
Vestnik KhNU 853 Pages. 22-27

The expression for the partial inner mutual admittance of two longitudinal slots overlapping along waveguide longitudinal axis is obtained. The slots are cut in a broad wall of a rectangular waveguide filled with three-layered dielectric. The excitation problem is solved with the modified eigen waves method. As eigen waves of the LE and LM modes are chosen. The field in the source region includes the potential functions as well. Dependences of inner mutual admittance and scattering parameters on distance between two slots and frequency are investigated. The system scattering parameters calculated are in a good agreement with experimental data


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36.  Influence of aperture-illumination law on near-field characteristics of aperture antennas
E.E. Ovsyannikova, A.V. Shishkova, N.N. Gorobets
electromagnetic waves, reactive fields, Aperture radiators, Kirchhoff technique, near-field, far-field, Amplitude distributions, phase characteristics, Amplitude characteristics, reactive radiation power
Vestnik KhNU 853 Pages. 28-36

On the basis of Hertz potentials the investigation of near-field reactive region of square aperture antennas with various aperture illumination laws has been carried out. The influence of the field amplitude distribution law in the aperture on the extension of this region has been studied. The calculation and analysis of amplitude, phase and power radiation characteristics, including reactive radiation power density, at the different planes in near-field region have been carried out. The analysis of the criteria for estimation of near-field reactive region boundary has been carried out


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37.  Single cone with longitudinal slots excitation by an impulse point source
A.V. Artyukh, y.A. Doroshenko, Y.D. Shimuk
impulse source, cone, longitudinal slots, Analytical solution, numerical solution
Vestnik KhNU 853 Pages. 51-56

In this work the excitation of a semi-infinite perfectly conducting cone with periodic longitudinal slots by an impulse radial source problem is investigated. The solution of the well-posed initial-boundary problem is found using an analytically numerical method based upon Green function and Meler-Fock integral transforms applying. It is shown that the original electrodynamic problem is equivalent to the one of the Fredholm linear algebraic equations system of the second kind solving. Analytical view of the solution is derived and the graphs illustrating the field dependence on the aperture angle and angle slot width are presented


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38.  Diffraction of the plane acoustic wave on the hard spherical segment, shielding of the ball
Rezunenko V.A.
Acoustics, spherical segment, shielding ball, resonance frequencies, Algebraic equations of the second kind
Vestnik KhNU 853 Pages. 57-63

A solution of the axisymmetrical problem of acoustics in strict formulation is built. The acoustic potential of the velocity of the plane wave, diffracted on the hard spherical circular segment, shielding of the ball is analyzed. The method of regularization of the paired summarized equations is used. The method of the integral transformations is applied. The principal part of the summarized equations is isolated and inverted. The effectively solvable system of the linear algebraic equations of the second kind with the compact operator in the Hilbert space l2 is obtained. Comparison with the known results and limited cases of the problem is given. The effectiveness of the constructed algorithm is confirmed. Some resonance frequencies and generalization of the task are examined


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39.  Asymptotic method of the solution of diffraction problem on the convex impedance cylinder, excited by the string of the electric current
V.I. Vyunnik, A.A, Zvyagintsev
diffraction, Asymptotic method, interpolation, convex impedance cilinder
Vestnik KhNU 853 Pages. 64-70

In the work considered the problem of diffraction electromagnetic waves on the convex impedance cylinder exited by string of the electric current, located near to its surface. The method asymptotic theories of the diffraction, offered by Fok is used. Are received asymptotic interpolation formulas for calculation radar cross section of the system string the current - cylinder, for a case of circular and elliptic impedance cylinders. The received formulas are suitable for calculations both in shadow and in lighted areas. It is shown, that these formulas can be distributed on a case of the any convex impedance cylinder with variable curvature


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40.  Analysis of impulse fields reflected from layered medium with losses using artificial neural network
Shyrokorad D. V., Dumin O.M., Dumina O.O., Katrich V.O.
time domain, Artificial neural network, impulse fields, layered medium
Vestnik KhNU 883 Pages. 35-40

The problem of determination of thickness a layer of layered medium by impulse irradiation is solved. The impulse fields reflected from the layered medium with electrical characteristics close to the characteristics of human skin are analyzed by artificia


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41.  FREQUENCY MULTIPLICATION AT IMPUCT IONIZATION IN TRASFER ELECTRON DIODES ON BASIS AlN, InN
E. D. Prokhorov, O.V. Botsula, I. A. Grishchenko
AlN, GaN, InN diodes, frequency transformation factor , drift velocity, harmonics.
Vestnik KhNU 883 Pages. 30-34

Multiplication of frequency at impact ionization in intervalley transfer electron diodes on basis InN, AlN is considered. The current voltage characteristics of intervalley transfer electron diodes have negative conductivity region and strong increasing


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42.  Longitudinal slot in a rectangular waveguide with dielectric layer parallel to wide walls
A.A.Liakhovskyi
slot, microwaves, waveguide, dielectric, Admittance, scattering parameters.
Vestnik KhNU 883 Pages. 59-66

The longitudinal slot is cut in wide wall of rectangular waveguide with three-layer dielectric filling which parallel to wide wall is considered. The excitation problem is solved with modified eigen waves method. As eigen waves of the LM- and LE- modes ar


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43.  ABOUT SPURIOUS RESONANCES IN PROBLEMS OF DIFRACTION WAVES ON WAVEGUIDE DISCONTINUITY
Mizernik V.N., Shmat'ko A.A.
spurious resonances, A branching of the waveguides, mathching uniformity, connection area, system of the linear algebraicequations
Vestnik KhNU 883 Pages. 67-72

In work it is shown, that the problem of existence of spurious resonances in problems of diffraction waveguide waves on various discontinue in waveguides is connected with incorrect representation of matrix elements of system of the linear algebraic equat


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44.  The accumulation of gas in galactic objects
Sorokin A.A., Sorokin A.F., Zaharova M., Sokolova O.V., Gorobets N.N.
Astrophysics, galactic objects, the accumulation of gas
Vestnik KhNU 883 Pages. 3-7

The mechanism of the accumulation of gas in the galactic objects submerged in the large-scale magnetic field is examined. As a consequence of the diamagnetism of the plasma subsystem of object, the stopper geometry of magnetic field with the radial electr


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45.  Own magnon polariton surface modes in the open passage resonator with gyromagnetic medium
Mizernik V.N., Shmat'ko A.A.
magnon polatiton oscillations, the ferrite resonator, A junction of waveguides, the through passage open resonator, wavegaide inhomogeneity, Area of connection, system of the linear algebraic equations.
Vestnik KhNU 966 Pages. 31-36

The problem about owen modes of the open reentrant resonator partially filled is theoretically solved by gyrotropic ferrite medium and existence magnon polatiton surface (PS) mods with tall concentration of a field on boundary line of the ferrite resonator is established. The every possible combined regimes of existence of superficial and volumetric fashions are analysed, dependences of their resonant frequencies on material parameters of medium and geometrical sizes of the resonator and a ferrite layer are certain.


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46.  Impedance characteristics of planar diodes with tunnel boundaries based on GaAs
Prokhorov E.D., Botsula O.V., Klimenko O.A.
: negative differential conductivity, tunnel boundary, A diode, the tunneling.
Vestnik KhNU 966 Pages. 13-18

The impedance characteristics of the diodes are consider, which negative differential conductivity (NDC) is arise under cer-tain voltage, due to tunneling of electrons through the side faces of the diode, which can be used for generation, amplification and multiplication. Depending on the active and reactive components of impedance are determined of the diode with the tun-nel boundaries for the real parameters of the diodes. It is shown that the limiting frequency of the diode NDC is in the tera-hertz range and depends on its parameters.


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47.  

Astrophysics, galactic objects, the accumulation of gas
Vestnik KhNU 883 Pages. 3-7

The mechanism of the accumulation of gas in the galactic objects submerged in the large-scale magnetic field is examined. As a consequence of the diamagnetism of the plasma subsystem of object, the stopper geometry of magnetic field with the radial electric field is formed. In this configuration, effective retention and the accumulation of the plasma, which revolves in the lattice-type fields, occurs. Atoms are tightly connected on the effects of recharge with the ions, which provides their accumulation. The calculated distributions of molecular and atomic hydrogen in our Galaxy, whose the stopper geometry of its magnetic field is well-known, are given. It is shown that this mechanism describes well the basic special features of gas subsystems


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48.  

AlN, GaN, InN diodes, frequency transformation factor , drift velocity, harmonics.
Vestnik KhNU 883 Pages. 30-34

Multiplication of frequency at impact ionization in intervalley transfer electron diodes on basis InN, AlN is considered. The current voltage characteristics of intervalley transfer electron diodes have negative conductivity region and strong increasing current regions due to impact ionization that is nonlinearity and lead to transparent frequency. If impact ionization takes place, frequency transformation factor increases and reaches, for example, 40 % for second harmonic have being showed. The frequency transformation factor increases for second and third harmonic if first harmonic voltage amplitude is several threshold voltage if compare with frequency transformation factor for all nitride compounds.


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49.  

time domain, Artificial neural network, impulse fields, layered medium
Vestnik KhNU 883 Pages. 35-40

The problem of determination of thickness a layer of layered medium by impulse irradiation is solved. The impulse fields reflected from the layered medium with electrical characteristics close to the characteristics of human skin are analyzed by artificial neural network in time domain directly. The normal incidence of plane wave with Gaussian time form is considered. The reflected electromagnetic field is calculated by FDTD method. Initial data for the neural network analysis are the values of amplitude of electrical component of reflected field. As an example, the network is trained to determine the thickness of one of the layers of the medium. The stability of the determination in presence of interferences, experimental errors and instabilities of medium parameters is investigated.


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50.  

slot, microwaves, waveguide, dielectric, Admittance, scattering parameters
Vestnik KhNU 883 Pages. 59-66

The problem of a longitudinal slot radiation is cut in wide wall of rectangular waveguide with three-layer dielectric filling which parallel to wide wall of a waveguide was solved. The excitation problem is solved with modified eigen waves method. As eigen waves of the LM- and LE- modes are chosen. The field in the source region includes the potential functions as well. The scattering parameters and resonance properties of slot are investigated. The scattering parameters calculated are in a good agreement with experimental data.


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51.  

spurious resonance, A branching of the waveguides, matching uniformity, connection area, system of the linear algebraic equations.
Vestnik KhNU 883 Pages. 67-72

In work it is shown, that the problem of existence of spurious resonances in problems of diffraction waveguide waves on various discontinue in waveguides is connected with incorrect representation of matrix elements of system of the linear algebraic equations (SLAE) which lead to features at their numerical decision. On an example of a problem of diffraction waveguide waves on the -branching of rectangular wave guides it is shown, that spurious resonances correspond to resonances of area of connection of waveguides. This computing mistake can be rather simply corrected due to correct representation of matrix elements SLAE which has no features. Results of calculations have shown efficiency of such approach for the decision of problems on own oscillations and problems of diffraction on the -branching of hollow wave guides, and tees with dielectric and ferrite resonators in the field of connection of waveguides.


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52.  

laser radiation, Acoustic emission, plasma, crater, A zone of non-elastic destruction, laser-plasma evolution.
Vestnik KhNU 983 Pages. 11-17

Acoustic emission of a zone of the destruction formed during influence of pulse laser radiation on a surface of metal is considered. Dependence of the time form of acoustic fluctuations on parameters of an irradiated material and the law of increase in depth of a crater was estimated. It is revealed, that at action on a surface of the copper sample of a laser impulse duration 20 ms time of growth of a zone of destruction makes approximately 40 ?, that will well be coordinated with time of existence of plasma formation at a surface of the target exposed to laser-plasma processing (50 ms).


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53.  Impact of random variations of air hole diameters and random variations of the centers position of air holes on operation parameters of a solid core microstructured optical fiber
A.I. Filipenko, A.N. Donskov
finite-element method, Gaussian distribution, inclusions diameter, total mode field power, Angular positioning, microstructured optical fiber.
Vestnik KhNU 983 Pages. 29-32

We investigated the impact of random variations of air hole diameter and random variations of the centers position of air holes on operation parameters in the case of solid core microstructured optical fiber with a ring of air holes. The found results show that at any of considered defect types mode field will have two pronounced maximums. At practical use an investigated type of the MOF special angular positioning end faces of fibers is necessary. We also have shown that random variations of inclusions diameter can increase total mode field power. In our research we used finite-element method.


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54.  

Abnormally low reflection, metamaterials, Antireflection channels.
Vestnik KhNU 983 Pages. 102-106

The physical features analysis to describe formation the regions with extremely low reflection of electromagnetic radiation in the terahertz and far infrared ranges are presented and these regions should be observed in many experimental studies. It is shown that in case of sufficiently small damping of polar phonon the spectral bands with almost complete reflection disappearance (R <0.01%) are formed and we name these bands as antireflection channels (ARC). ARC located outside the region of negative dielectric permittivity, and the minimum reflection is shifted above the frequency of longitudinal oscillations by the value depends on the basic parameters of the polar vibrations.


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55.  

Antenna array, horizontal polarization, double slots, slowing system.
Vestnik KhNU 927 Pages. 54-58

Energetic and directional characteristics of an antenna array (AA) with single transversal slots and double ones cut in a rectangular waveguide, partially filled with dielectric are investigated. In the case of single transversal slots and double transversal slots a dielectric layer is parallel to broad walls of the waveguide. It was shown the possibility to construct an AA with double transversal slots having the pattern without diffraction lobes and high level of radiation power in the wide frequency band.


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56.  

slot, waveguide, dielectric, Admittance, scattering parameters, slot-waveguide array.
Vestnik KhNU 927 Pages. 59-64

The scattering problem of a longitudinal slot system is cut in wide wall of rectangular waveguide with three-layer dielectric filling which parallel to wide wall of a waveguide was solved. The scattering parameters and gain of linear slotted-waveguide array are investigated in range of frequency. The gain optimization and synthesis of linear slotted-waveguide array were carried out using a genetic algorithm. The obtained gain weakly depends from frequency.


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57.  

polarization converter, Bragg reflector, Anisotropy
Vestnik KhNU 927 Pages. 43-47

Today, there are two fundamental type polarization converters, passive and active, are widely used in optical circuits. In this paper, we present a passive polarization converter for near infrared range. The converter reported here is porous silicon-based structure consists of N distributed Bragg reflectors (DBR) separated by N-1 defects. The method of the electromagnetic fields scalarization and finite difference technique were used for calculation of spectral characteristics. The transmittance spectra of the proposed polarization converters for the both polarization of the incident plane wave are presented


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58.  

Gunn diode, dipole domain, Accumulation layers, transit frequency, efficiency generations
Vestnik KhNU 927 Pages. 3-6

Results of research of power and frequency characteristics of Gunn diodes on the basis of Al1-xInxN for various values of concentration of impurity in active area in biharmonic regime are present. It is shown, that using of voltage of the complex form leads to increase of efficiency generation at the basic harmonic in comparison with work in harmonic regime. The increase of impurity concentration in active area leads to increase of efficiency generation both on the first, and on the second harmonic. At the expense of effective work on the second harmonic there is a possibility of reception of generation to frequencies of a submillimetric range.


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