Kharkov National University
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1.  Complex dielectric permittivity of disperse heterogeneous systems and their components
L.M. Atroshenko, N.N. Gorobets, L.P. Safronova
complex dielectric permittivity, disperse system
Vestnik KhNU 712 Pages. 8-16

The relationship between complex dielectric permittivity of two-component disperse system, its components' volume shares and dielectric permittivity has been obtained. The method for computation of volume shares and dielectric permittivity of water solution hydrated inclusions is suggested



2.  Method of finding permittivity, volume characteristics and hydratation of components of water solutions
L.M. Atroshenko, N.N. Gorobets, L.P. Safronova
dielectric permittivity, bound water, hydration, specific volume, density
Vestnik KhNU 712 Pages. 17-20

A method for calculation of permittivity of bound water, hydration of substances, volume shares and specific volumes of water solution components, based on data of measurements of the complex permittivity and solution densities, was suggested



3.  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



4.  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



5.  Telemetering methods, devices and their application in vertebrology
S.N. Kulish, O.Y. Kagan
radiotelemetring research, transmitter, radio channel, implant devices, spine, impellent segments
Vestnik KhNU 712 Pages. 33-36

In the given job the review and the analysis of existing telemetering methods of research and diagnostics of various diseases in medicine is resulted. It is offered to use means of radiotelemetering research for registration of mechanical parameters arising on contact and lateral surfaces of impellent segments of a backbone. The block diagram of multichannel telemetering system is resulted and the basic requirements shown to this system are described



6.  Radiation from dual-mode circular waveguide excited by dominant and higher-order modes simultaneously
A.V. Shishkova, N.N. Gorobets
microwaves, multimode waveguide, diffraction, higher-order modes, Weinstein rigorous technique, Wiener-Hopf technique, radiation pattern.
Vestnik KhNU 712 Pages. 56-61

On the basis of Weinstein rigorous solution to the problem of electromagnetic mode diffraction at an open-ended circular waveguide the characteristics of radiation from multimode waveguides excited by H11 dominant mode and. higher-order modes (E01, and H01) simultaneously are calculated and analyzed. The calculation of radiation from waveguide with dual- mode excitation is carried out in the whole observation space and in wide frequency bandwidth, taking into account the higher-order mode transformation and currents leaking on the external surface of a waveguide.



7.  Integral representation of green function in parallel-plate and rectangular waveguide, and in resonator as well
V.A. Katrich, F.S. Novokhatsky
waveguides, Green function, fundamental solution, radial function, elliptical teta- function, image method, calculus of residues, integral transformation, grating, formal variative
Vestnik KhNU 712 Pages. 67-70

The known results connected with Green function representation by elliptical theta-function are generalized. New representations of Green function for some widely used types of waveguides are obtained. Earlier, these Green functions are presented either in form of series with nonuniform convergence or in form of integrals containing Hancel functions, which are reduced to asymptotic expressions in far zone. On this work integral representations of Green functions are obtained for Cases where the quadrature formula exists. The method of analytical continuation with parameter is applied



8.  The influence of the inner chanal of a periodic iris-loaded circular waveguide concerning its eigenmode mutual transformations
He Shi, S.K. Katenev, S.N. Shulga
dispersion, Brillouin diagram, mode transformation
Vestnik KhNU 712 Pages. 80-83

The mutual eigenmode transformations are considered of a periodic iris-loaded circular waveguide against variations or its inner radius, using BriUouin diagram characteristics. The specific features of the waveguide regular and periodicity modes of Eo,and asymmetric waves are pointed out



9.  Analytical solutions in time domain for electromagnetic fields in a cavity with Debye medium
M.S. Antyufeyeva
dielectric, dispersion, Debye medium, electromagnetic fields in a cavity with a dielectric, evolutionary approach to electromagnetics, time domain
Vestnik KhNU 712 Pages. 84-90

The theoretical investigation of the properties of electromagnetic oscillations in a cavity with Debye medium is carried out. The problem is considered within the frame of the Analytical Approach to Electromagnetics in the Time Domain (TD), which allows obtaining closed-form solutions in TD for a wide range of electrodynamical problems. For the description of electromagnetic properties of the medium is used representation of the constitutive relation in an integral form. The analytical solutions are obtained for the several excited functions in TD and they validity conditions are defined. Characteristics of electromagnetic oscillations are presented for different relaxation time and dielectric susceptibility



10.  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.



11.  On the directive gain of the self-focusing antenna
Ya.S. Shifrin
directive gain, self-focusing antenna, inhomogeneities, structure function
Vestnik KhNU 756 Pages. 11-17

The influence of the atmospheric inhomogeneities on the directive gain of the self-focusing antenna array (SFAA) at description of the atmosphere by the theory of the local-isotropic turbulence is considered. There are analyzed two cases when a size of the SFAA subaperture is respectively more or less than the turbulence scale of the medium. It is shown mat the results of the meat directive gain estimation for the two cases are well conformed qualitatively with the analogous estimates obtained at the atmosphere description wife the help of the Gaussian correlation function of its refractivity index



12.  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



13.  ELECTRODYNAMIC MODELING OF COMPOSITE MEDIA WITH SIMALTENEOUSLY NEGATIVE REAL PARTS OF PERMITTIVITY AND PERMEABILITY
S.N. Shulga, I.E. Khodasevych
composite media, thin-wire resonance inclusions, permittivity, permeability, scattering of electromagnetic waves
Vestnik KhNU 756 Pages. 38-41

This paper presents physical and mathematical model and investigation of electromagnetic properties of composite material made of straight and curved conducting resonance inclusions placed into isotropic media and forming periodic lattice. The effective constitutive parameters of the composite material are found. It is revealed that on resonance frequency real parts of permittivity and permeability of such media can assume simultaneously negative values. The problem of reflection and transmission of plane electromagnetic wave through a sequence of layers made of such composite material is solved, numerical results are presented



14.  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



15.  One-dipole inverse problem of magnetostatics for reconstruction of heart-torso electric activity from magnetocardiography measurements
Bagatskaya O., Butrym A., Durneva Yu., Shulga S.
Do not determinated
Vestnik KhNU 756 Pages. 47-50

Do not determinated



16.  Electrons in superlattice with continuous conduction band edge
M.V. Klymenko, S.I. Petrov
superlattice, effective mass, Bragg effect, carriers confinement
Vestnik KhNU 756 Pages. 91-96

In this paper, the energy spectrum of electrons is investigated for the superlattice with continuous conduction band edge. The comparison with conventional superlattice has been realized. It is shown that in the investigated structure the energy spectrum has band structure which is caused by periodic position-dependent effective-mass. Moreover, position-dependent effective-mass leads to additional effective potential. The Bragg reflection for electrons in ballistic limit can be observed in the superlattice with continuous conduction band edge. It can be used for effective Bragg confinement of carriers. For the first time the investigations have been carried out for the case when the superlattice without band offsets has finite number of periods. The obtained results shed light on new applications of the investigated structures for THz frequency range



17.  Amplitude and noise features of detectors a mm of range of lengths of waves on base of contacts a metal-semimetal BiSb
O.N. Sukhoruchko, V.T. Plaksiy, E.D. Prokhorov, A.V. Dyadchenko
contact metal-semimetal BiSb, power zones, contact a metai-semimetal BiSb, millimeter range of lengths of waves, relative noise temperature, influence of displacing and resistances of contacts on sensitivity
Vestnik KhNU 756 Pages. 113-117

In work are brought results of analytical and experimental thermoelectrical detector study with the point contact a metal-semi-metal BiSb. Determined relative noise temperature, as well as influence of displacing and resistances of contacts on the sensitivity in 8 mm range of waves.



18.  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



19.  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



20.  RECTANGULAR WAVEGUIDE M.V.
O.N. Sukhoruchko
millimeter range, parametric amplifier, oscillatory system, band of the reinforcement, relative noise temperature
Vestnik KhNU 806 Pages. 18-21

Semiconductor two-stage parametric amplifiers have been developed to be used in the input circuits of communication and navigation systems in the short-part of millimeter wave band. In the 60 to 65 GHz range, the gain is no worse than 15 dB at -3 dB level in 1 to 1.6 GHz bandpass. The noise temperature is no higher than 500K when the quasi-optical IMPATT oscillator is in using as the pumping generator.


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21.  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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22.  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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23.  Thermo equilibrium and differential capacity of p+-n junction
N.A. Shekhovtsov
p+- n junction, distribution of potential
Vestnik KhNU 806 Pages. 48-53

The accurate distribution of field and potential in the region of abrupt p+- n junction under thermodynamic equilibrium is obtaned. The formula of p+- n junction width with any relation of mobile charge carrier magnitude and ion donors of n-region is obtained. The dependence of p+- n junction differential capacity upon out voltage, which does not need numerary methods is obtained. It was shown, that under direct and reverse switching of p+- n junction the dependence of capacity upon voltage is more complicated than for p- n junction in the depletion mode.


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24.  Thermo equilibrium state of p+-p junction
N.A. Shekhovtsov
p+-p junction, distribution of potential
Vestnik KhNU 806 Pages. 54-58

The thermo equilibrium state of p+-p junction with surface charge of p+-region was investigated. The distribution of field and potential in the region of such junction is describing by Poisson's equation with un-known charge distribution on coordinate. The solution method of this equation allowing to obtain precise distribution of field and potential on coordinate was proposed. The formula for width of p+-p junction with any ratio of mobile charge carriers and charge of ion-acceptors in p-region was obtained.


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25.  Theory of the millimeter waves o-type clinotron amplifier
E.N. Odarenko, A.A. Shmat'ko
nonlinear multidimensional theory, clinotron amplifier, electrons settling
Vestnik KhNU 806 Pages. 75-81

Nonresonant amplifier O-type system with inclined focusing field is considered. Theoretical investigation is carried out within the framework of the beam-wave interaction multidimensional model. Input signal power, focusing field magnetic induction value and electrons settling on the electrodynamical system surface are taking into account


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26.  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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27.  Application of the digital holographic interference microscope for investigation of thin films
D.N. Tishko, T.V. Tishko, V.P.Titar, Yu. A. Zadneprovskiy, A.S. Kuprin, I.A.Zgoda
digital holographic interference microscope, three-dimensional images, vacuum-arc method, thin AlN films
Vestnik KhNU 806 Pages. 99-102

For the first time the digital holographic interference microscope (DHIM) was used for investigation of thin films on transparent substrates. Three-dimensional images of AlN of thin films, deposited on acryl substrates by the vacuum-arc method have been obtained, their thicknesses have been measured. It has been shown that the DHIM can be successfully used for film surface quality checking, thickness and film damages parameters measurement.


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28.  Dispersive characteristics of magnetoplasma waves in the rectangular wave guide with InSb
O.A. Zamuraev, O.O. Puzanov, A.S. Tishchenko
magneto-plasma wave, semiconductor plasma, dispersive characteristics, nitric temperature
Vestnik KhNU 834 Pages. 3-7

Frequency dependence of characteristics of magnetoplasma waves in the rectangular wave guide, containing longitudinal and cross-section - magnetized the semiconductor at various sizes of an induction of a magnetic field is experimentally investigated. Areas of values of an induction in which the behavior of wave number and factor of attenuation has resonant character are determined. An existence of two superficial magnetoplasma waves which are distributed in opposite directions is experimentally confirmed in longitudinal - magnetized semiconductor plasma. Good concurrence of results of experiment and numerical calculations is shown


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29.  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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30.  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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31.  Target size and shape identification by multifrequency radar measurements E. V. Ryeznik, O. I.
Sukharevskiy, A. G. Tyzhnenko
iceberg, shape and size identification
Vestnik KhNU 834 Pages. 31-36

A new method identification of targets shape and size is proposed. In this method, the values of RCS measured on the set of discrete frequencies are compared with the theoretical ones on the same set for canonical group of target configurations (patterns). 2D patterns implementation is considered instead of 3D patterns for the sake of scattering problems simplification. To this end, 2D RCS were transformed to 3D RCS under definite conditions. The method is implemented to the iceberg identification problem in model approach


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32.  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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33.  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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34.  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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35.  Electromagnetic waves focusing inside dielectric cylinder
N. N. Gorobets, N. N. Stasjuk
microwaves, dielectric cylinder, plane wave, focusing points
Vestnik KhNU 834 Pages. 77-84

Computation and analysis of electrical and magnetic field amplitudes at focusing points inside dissipative dielectric cylinder illuminated by plane linear polarized wave have been performed using the approximation of geometric optics. It was shown that in the focal region fields vary according to oscillating law and field longitudinal gradients the more cylinder diameter and dielectric permittivity, the large at that. Results of investigation allow to explain subthreshold (nonthermal) exposure of millimeter and submillimeter electromagnetic waves on human and other biological objects


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36.  Near electromagnetic field of combined waveguide-slot radiators in matter
S.L. Berdnik, V.A. Katrich, M.V. Nesterenko, S.V. Pshenichnaya
rectangular waveguide, waveguide-slot radiator, material medium, hyperthermia, Galerkin's method
Vestnik KhNU 834 Pages. 85-88

The problem about the electromagnetic waves radiation into the homogeneous isotropic medium by the system of combined waveguide-slot radiators in the broad wall of a rectangular waveguide has been solved in a rigorous self-consistent formulation. The spatial distribution of the near field intensity in the half-infinite material medium with the electrophysical parameters, corresponding to some man's tissues, has been investigated


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37.  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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38.  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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39.  Algorithm of a pulse signals delay definition, based on a Hilbert's transformation
D.O. Batrakov, D.V.Golovin, S.V. Grekov, A.G. Batrakova*
pulse signals, definition of a delay of signals, Hilbert's transformation, plane-layered media, thickness measurements
Vestnik KhNU 853 Pages. 71-76

In the present paper the algorithm of processing of the pulse signals reflected from plane-layered media is offered. It is supposed, that an effective thickness of layers less than spatial size of an impulse. This feature of a problem complicates use earlier proposed methods of signals time delay evaluating. Therefore in paper the theoretical analysis of possibilities of various approaches for processing of signals is carried out and the algorithm and the corresponding software for definition not only a time delay, but also physical and geometrical characteristics of investigated objects are offered. Results of numerical modelling and experimental researches for the purpose of definition of sensitivity and resolution of a method, and also possibility of its practical use are given


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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.  Investigation of different temperature modes of auxilliary cathode work in magnetrons with cold secondary-emission cathode
Avtomonov N.I., Vavriv D.M., Sosnytsky S.V.
Magnetron, cathode, thermionic cathode, thermo emission, temperature
Vestnik KhNU 883 Pages. 73-82

A theoretical investigation of the emission current temperature dependence of the auxiliary cathode in magnetrons with cold secondary-emission cathodes is performed. Different methods of providing a spatial-charge limited emission from the auxiliary catho


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42.  Quantum efficiency spectral chracteristics of resonant cavity photodector taking into account thermal gradient
S.V. Gryshchenko,
Resonant cavity photodetector, refractive index, temperature shift
Vestnik KhNU 883 Pages. 8-11

In paper a theoretical analysis of quantum efficiency of resonance InGaAs/GaAs P-i-n photodetector (RCE PD) is presented. A mathematical model plugs in itself the transfer matrix method, heat conductivity calculation and dependence of index of refraction


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43.  Determination of optimal parameters of a magnetocardiographic hexagonal measuring grid
A.Yu. Kostiev, A.Yu. Butrym, S.N. Shulga
magnetocardiography, gradiometer, current dipole, sensitivity, Hessian
Vestnik KhNU 883 Pages. 25-29

The article considers hexagonal grid of gradiometer sensors of magnetic field. The aim of the study is to determine the optimal parameters of the grid and the gradiometers in order to obtain maximum sensitivity of the measuring system in terms of location


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44.  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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45.  Ballistic electronic transport in continuous-band superlattice under applied electrostatic field
S.I.Petrov, Klymenko M. V., Shulika O. V.
ballistic transport, superlattice, effective potential
Vestnik KhNU 883 Pages. 12-19

We address in this work ballistic transport of electrons in semiconductor continuous-band superlattice under applied electrostatic field. Combined influence of the effective mass periodically varied in space and external electrostatic field on the electro


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46.  Dielectric permittivity profile reconstruction by frequency probing problem for a plane-layered media with regard to dispersion
Batrakov D.O., Simachov O.A.
plane layered media, dispersion, inverse problem, dielectric permittivity
Vestnik KhNU 883 Pages. 45-49

In the present paper the problem of dielectric permittivity profile reconstruction with regard to dispersion is discussed. The nature of dispersion function is assumed to be known and unknown functions are real and imaginary parts of dielectric permittivi


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47.  Microstrip structures with photonic band gap
Fesenko V.I., Sukhoivanov I.A., Shul'ga S.N.
photonics band gap, microstrip, filter
Vestnik KhNU 883 Pages. 20-24

In this paper, it is presented a two-sided one-dimensional photonic bandgap microstrip structure. The structure is obtained by etching a one periodic pattern of circles in the ground plane of a microstrip line and variation of the characteristic impedance


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48.  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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49.  NonstationarY processes in the hybrid O-type beam-wave system
Odarenko E.N., Shmatko A.A.
nonautonomous oscillatory system, locking, beats
Vestnik KhNU 966 Pages. 23-30

Nonstationary processes in the resonant beam-wave system with pre-modulated electron beam are investigated in this work. Theoretical analysis is performed on the basis of the nonlinear multidimensional theory of the hybrid O-type electron devices. Basic regularities of the external signal power effect on the lock range width are described. Regimes of the oscillations synchronization, beats and squitter for different values of the oscillation system and ex-ternal signal parameters are considered.


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50.  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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51.  Polarization and energy characteristics X-slots in the waveguide with the complex load and the dielectric inserts
Blinova N.K., Yatsuk N.N., Selyutin A.V.
-slots , ellipse coefficient, VSWR level , circular polarization.
Vestnik KhNU 966 Pages. 77-81

The -slots in a rectangular waveguide with the end complex loading and dielectric inhomogeneity at the waveguide input are considered. Calculation and experimental results of power and polarization descriptions are carried out for such systems. The possibilities of polarization and power characteristics of -slot control are investigated. The variation of dielectric inhomogeneity and complex end loading parametors allows to obtain the circular polarization, high radiation coefficient and low VSWR level


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52.  Determena Frequency properties of intervalley electron transfer in AlN
V. T. Plaksiy, .V.Arhipov, . S. Tischenko, . . Kamishanova, E.D. Prokhorov, .V.Dyadchenko, D. P.Chueshkov
perfect crystal, zone overcrystallization, temperature gradient
Vestnik KhNU 966 Pages. 19-22

The problem of growing of perfect bismuth-antimony monocrystals having of a uniform distribution of Sb atoms through the crystal by help floating-zone refining method is considered. The expression for temperature gradient in melt and temperature distribution for any melt point have been obtained. The monocrystals growing maximal velocity have been estimated. The growing velocity must be lower then 1 mm per hour was showed. It is velocity not lead to concentration overcooling and arising inhomogeneous dendrite structure. For solution with certain composition ( at = const) overcooling may be eliminated by either increasing of temperature gradient in liquid faze or decreasing growing velocity are showed.


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53.  
Lizogubenko S.V., Kokodiy N.G.
scattering pattern, diameter of the particles, scattering, brightness of the light spot, beam intensity
Vestnik KhNU 966 Pages. 9-12

Considered the method of defining the size of microparticles using a digitized image of the scattering. For research the optical method is used It consists that the researched substance, consisting of microparticles, is illuminated with the beam of optical radiation and then the scattering of the transmitted light is registered. After this, the digital processing of resulting scattering pattern is carried out and held the measurement of particle size in two different ways.


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54.  The geometrical approaches to the calculation of propagation of Gaussian beams in hollow metal waveguides in the terahertz range
Gurin O.V., Degtyarev A.V., Maslov V.A., Svich V.A., Senyuta V.S., Topkov A.N.
metal waveguide, Gaussian beam, terahertz range, geometrooptical approach, transmission coefficient
Vestnik KhNU 966 Pages. 3-8

A comparison of the results of calculations of the transmision for Gaussian beams in hollow circular metal waveguide using geometrooptical procedures by Frost and Crenn with the results of experiments in the terahertz range is performed. The conditions of applicability of these methods to study the transmission characteristics of metallic waveguides of different lengths were found. It is shown that in this range the geometrooptical approach, proposed by Frost, provides satisfactory results only for short waveguides, the length of which corresponds to the condition of the near zone. The geometrooptical approach by Crenn is applicable to both short and for long waveguides.


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55.  
magnetocardiography, gradiometer, current dipole, sensitivity, Hessian

Vestnik KhNU 883 Pages. 25-29

The article considers hexagonal grid of gradiometer sensors of magnetic field. The aim of the study is to determine the optimal parameters of the grid and the gradiometers in order to obtain maximum sensitivity of the measuring system in terms of location of a pointwise dipole source of magnetic field in some spatial region. These parameters are the distance between adjacent gradiometers in the grid (base of the grid) and the distance between two coils within gradiometer (base of the gradiometer). The obtained results allowed us to formulate some recommendations regarding design of such magnetocardiographic measuring system.


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56.  The xecl laser with the adjustable shape and duration of generation pulse
S.S. Anufrik, A.P. Volodenkov, K.F. Znosko
LC- contour, XeCl laser, excitation system, generation energy, pulse duration.
Vestnik KhNU 983 Pages. 3-10

The generation parameters of LC-contour excitation system are studied for electro-discharge excimer XeCl laser using a NeXeHCl mixture. A computation model is developed for finding the generation parameters. It has allowed us to calculate current, voltage and generation power oscillograms for all parameters of the electrical excitation system. The program of XeCl-laser modeling enables to calculate an electrons, atom and molecule concentrations, specific energy deposition in active medium also. By means of program Bolsig + calculation of rate coefficients of reactions with participation of electrons is executed. It is shown that generation of short radiation pulses (20 ns) and relatively long pulses (60 ns) is possible due to changing of LC- contour parameters. Energy of generation reaches a maximum at use of small values of peaking capacity, which are significantly smaller then value of storage capacity.


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57.  Light propagation characteristics of optical metal dielectric coaxial nano-waveguides with complex shapes
O.N. Kozina, I.S. Nefedov, L.A. Melnikov
plasmonic waveguides, coaxial, noble metals, numerical simulations, nano-size.
Vestnik KhNU 983 Pages. 48-53

The properties of new optical waveguides with nanosize cross-section made of noble metals and glasses are described. This waveguide supports propagation of modes with unusual propagation properties. For estimation of the field localization, losses, propagation length, velocity and others characteristics the numerical simulations by FEM method has been used. Coaxial waveguide with the annular and the elliptic central rods are considered. The comparatively low value of losses has explained.


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