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V.N.Karazin
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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.  Radiation of transient fields from the open end of coaxial waveguide with shifted internal conductor
N.N. Gorobets, A.N. Dumin, O.A. Dumina
transient field, coaxial waveguide with shifted internal conductor, TEM-wave, radiation
Vestnik KhNU 712 Pages. 42-46

The problem of the radiation from the open end of coaxial waveguide with shifted internal conductor excited with transient source is solved in time domain. The incident into the aperture TEM-wave in coaxial waveguide with time dependence in form of gaussian pulse is considered as a source. The influence of a flange on radiated field characteristics is examined. The application of dielectric insertions into the aperture for the increasing of radiation along normal to aperture is studied



4.  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.



5.  Features of forming patterns of planar antennas arrays
A.A. Bulgakova, N.N. Gorobets, V.A. Katrich, V.A. Lyashenko
planar arrays, pattern, sidelobes, radiator elements, interference maximums triangular grid
Vestnik KhNU 712 Pages. 71-75

Computer analysis results of an influence of a radiating aperture form of the planar array on its pattern have been presented. It is shown that there is dependence of levels of interference lobes and also near and far sidelobes of pattern in one of main positions of observation planes on number and radiators in plane which is orthogonal to main observation plane



6.  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



7.  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



8.  ONBOARD RADIOHOLOGRAPHIC INFORMATION SYSTEM of DISTANT ACTION CREATED ON THE BASIS OF APPLICATION of middle-aperture SPHERICAL antenna
I.V. Baryshev, N.N. Gorobets, N.I. Matjuhin
radioholography, multiitem coherent systems, middle-aperture spherical and ring antennas, range of direct visibility
Vestnik KhNU 756 Pages. 18-21

Basic opportunities of creation of perspective radioholographic information system which is capable to carry out full radar-tracking service of a stream of the objects which are taking place on big distance are considered, and on small distance - to receive their radioholographic image. Formulas for calculation of the antenna pattern are received depending on number of elements of the antenna which determine a level of its side lobes



9.  ONBOARD RADIOHOLOGRAPHIC INFORMATION SYSTEM of DISTANT ACTION CREATED ON THE BASIS OF APPLICATION of middle-aperture SPHERICAL antenna
I.V. Baryshev, N.N. Gorobets, N.I. Matjuhin
radioholography, multiitem coherent systems, middle-aperture spherical and ring antennas, range of direct visibility
Vestnik KhNU 756 Pages. 22-26

Basic opportunities of creation of perspective radioholographic information system which is capable to carry out full radar-tracking service of a stream of the objects which are taking place on big distance are considered, and on small distance - to receive their radioholographic image. Formulas for calculation of the antenna pattern are received depending on number of elements of the antenna which determine a level of its side lobes



10.  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.



11.  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



12.  SCATTERING AMLITUDE ERROR ESTIMATION FOR MOMENT'S METHOD IN L2 FOR 2-D SCREENS
A.G. Tyzhnenko, Y.V. Ryeznik
testing, reference solution, moment's method, 2-D screens
Vestnik KhNU 756 Pages. 65-70

The scattering amplitude error estimation problem for practically used MoM solutions in L2 function space for scattering from 2-D screens is addressed. To this end, a rigorous Galerkin solution in L2 to logarithmically singular and hypersingular EFIE is used as a reference solution for scattering amplitude error estimation by benchmarking. This one requires substantially lower computational efforts than using of the same MoM algorithm but with very high mesh density as a reference solution. To many, the approach helps to avoid unpredictable errors due to the ill-conditioning connected with high mesh density for any MoM solution to the EFIE in L2. Using the approach, the asymptotic decay rate of scattering amplitude error is investigated for some MoM algorithms widely used in practice



13.  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



14.  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



15.  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



16.  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.



17.  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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18.  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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19.  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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20.  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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21.  Identification and localization of radar impulses buried in noise
A. G. Tyzhnenko, Y. V. Ryeznik
radar, pulse, identification, localization, low SNR
Vestnik KhNU 806 Pages. 70-74

Statistical method identification and localization of radar impulses buried in noise is addressed. To this end, the correlation coefficient between carrier samples measured in the extremal points and analogous set of points of received signal is proposed to implement. Such measurements for receiving signal need to be done at least by one tenth of the half period of the carrier. Because of very simple algorithm proposed, such measurements do not lead to heavy computational burden. To decrease identification and localization errors for given signal to noise ratio (SNR) one needs to increase the number of measurements points, and hence, the pulse width. To prevent this issue, one can increase the carrier frequency. In general, the method accuracy increases with the carrier frequency. The method proposed permits theoretically to identify with fidelity impulses buried in noise for SNR lower than -30 dB.


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22.  Spatial and temporal features of the midlatitude total electron content
I. G. Zakharov
total electron content, dual-frequency Doppler shift measurements, planetary waves
Vestnik KhNU 806 Pages. 82-86

Experimental study of the latitudinal and diurnal variations in the total electron content over Eastern Europe are present. The dual-frequency Doppler shift measurements from navigation satellites and incoherent scatter radar (ISR) data are used The ISR data were collected near Kharkiv city (49.6oN, 36.6oE), and the dual-frequency signals from navigation satellites in circular polar orbits at the altitude of about 1000 km were received at the Kharkiv V. Karazin National University Radiophysical Observatory (49.6oN, 36.3oE). The calculated total electron content maps span the 35o 65oN geographic latitude range and the 24-hour local time range. These maps and other data represent all known features of diurnal and latitudinal total electron content variations at middle and subauroral latitudes, and in particular, they represent the local latitudinal maximum at 50oN geographic latitude in total electron content. The results obtained also indicate that tidal and planetary-scale waves act to noticeably modify the temporal and spatial variability of TEC, including that under quiet conditions.


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23.  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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24.  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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25.  Fields of the rectangular loop antanna in near-field zone
N.N. Gorobets, .V. Trivaylo
electromagnetic waves, radiation, near-field zone, Hertz vector, traveling wave antenna, loop antenna
Vestnik KhNU 834 Pages. 18-24

On the basis of potential Hertz technique the expressions for calculating of all components of electromagnetic radiation fields of rectangular loop antenna, stimulated by the running wave of the current in Spherical and Cartesian coordinate systems unrestricted on the size of radiator and distance up to a point of observation have been derived. It has been shown that in a near field zone of radiation electromagnetic vectors in the Cartesian and Spherical coordinate systems have all 6 component. It has been shown that wave processes near by the examined radiators are distinguished by great gradients of amplitudes of the electromagnetic fields


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26.  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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27.  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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28.  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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29.  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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30.  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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31.  Potentially unbreacable ciphering on a hybrid physical-mathematical level
A. G. Tyzhnenko, E. V. Ryeznik
bit, stochastic signals, safe communication, hard drive protection
Vestnik KhNU 834 Pages. 108-113

A new kind of ciphering based on stochastic representation of bits as series of samples is addressed. Stochastic comparison is used for bit identification. Security level is increased by adding noise samples to signal samples and mixing signal samples with noise samples within one signal packet. The signal packet length and distribution features of signal samples among noise samples in signal packets are unique for given communication line, as well as stochastic representation of bits (0s and 1s). Using of noise in signal packets leads to enormous large computation in decrypting process which is unrealistically to do regardless what computer system is used. More to the point, the unique features of communication line mentioned above can be changed for each message that prevents information leakage in the case of stealing these ones in any previous period. Impossibility of decrypting by any reasonable time period of any message eavesdropped by a cryptanalyst guarantees the confidence of information which has permanent importance


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32.  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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33.  Algorithms of the processing signal from the trellised receiver for measuring of the laser radiation characteristics
Kokodiy N.G., Pak A.O.
the laser, optical radiation, intensity, bolometer, direct task, reverse task
Vestnik KhNU 853 Pages. 37-44

In this paper has been considered the development of the device for the measurement of the intensity distribution in the beam of optical radiation. The algorithm of processing of a signal from the receiver of radiation is studied. The method of measurement of the intensity distribution of optical radiation by the bolometric grid is offered. The developed algorithms for processing a signal from the measuring converter and programs realizing them are checked up experimentally, their serviceability is confirmed. The comparative characteristic of algorithms based on the transformation of Fourier and transformation of Radon has shown an opportunity of their use in practice


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34.  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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35.  Theoretical investigation of photonic crystals by means of analysis of photonic density of states maps
I.V. Guryev
photonic crystal, photonic density of states, transmittance spectrum, plane wave expansion method, finite differences method
Vestnik KhNU 853 Pages. 77-83

In the work, there have been computed the photonic density of states maps of the 2D photonic crystal by means of plane waves expansion method by the analogy with photonic band gap maps. The photonic density of states maps allows precise determination of the parameters of photonic crystals during the design process of the photonic crystal-based device. Moreover, there have been carried out the comparison with analogous characteristics obtained by the finite differences time domain method. Comparison results indicate the similarity of results obtained by two methods, however, the computation of photonic density of states maps requires much less time at the same computation precision. Moreover, in the work there have been carried out the comparison between the efficiencies of the photonic density of sates maps and the photonic band gap maps analysis methods


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36.  Random inhomogeneous liquid medium as a continuous laser of low-intensity modulator for excitating sound in the medium
B. G. Yemets
laser, random inhomogeneous liquid medium, interference, temperature field, optical acoustical phenomenon, sound, excitation, modulation
Vestnik KhNU 853 Pages. 95-100

When a medium is irradiated by laser pulses, sound waves are excited in this medium, i.e., the well-known optical acoustical phenomenon occurs. To excite sound oscillations, the specific laser beam modulator is shown to be unnecessary. The role of the modulator can play the liquid itself, which is a random inhomogeneous medium. The real liquid contains suspended solids and gas bubbles of small dimensions (dust particles and the like) that move irregularly in space (fluctuations). As a result, the electromagnetic wave interference taking place in the liquid undergoes random changes. Consequently, the temperature field changes, and hence variations in the local pressure occurs (thermo-optical mechanism for exciting sound). The excitation of sound due to the laser irradiation of low intensity is observed in an increase in the gas bubbles dimensions in the liquid


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37.  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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38.  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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39.  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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40.  Compromising emanations: overview and system analysis
N.N. Gorobets, .V. Trivaylo
compromising emanations, near-field-zone, electromagnetic, radiation, time domain
Vestnik KhNU 883 Pages. 83-88

The problem of compromising radiation of spurious signals in the near, intermediate and far zones of observation in time domain are considered. The Compromising emanation system analysis for finding spurious radiation is proposed. The goal of the given approach is to speed the development of technical protection of information. In approximation of the given current distribution it has been suggested a solution considering the influence of the near-field effects upon directional characteristics of spurious signals radiation. The application of the new method allows us to investigate compromising of technical means in time and frequency domain.


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41.  Analysis of polarization characteristics of electromagnetic waves in non-orthogonal linearly polarized basis
Gorobets N.N., Chekalin , Chekalina G.N.
lectromagnetic wave, electric field strength,time-distance curve, harmonic basis, the expansion of the harmonic, the polarization model
Vestnik KhNU 966 Pages. 50-55

We solve the problem of determining the polarization characteristics coefficient of ellipticity and orientation angle of the polarization ellipse and the direction of rotation of the polarization vectors of linearly polarized basis with arbitrary angle between the components of the electromagnetic wave. In the special case of orthogonal linearly polarized basis obtaind solutions coincide with the known one. An algorithm for constructing a model of elliptically polarized waves had been elaborated in this article as the totality of hyperbolic and elliptic circles.


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42.  
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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43.  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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44.  Influence of shading of the radiating aperture of single-reflector antenna by focal module on directional characteristics
Gorobets N.N., Kiyko V.I.
microwaves, reflector antennas, reflector shading, directional characteristics
Vestnik KhNU 966 Pages. 97-102

The effect of shading of the radiating aperture single-reflector parabolic antenna on radiation pattern, gain, wide beamwidth and sidelobe levels while changing the focal length of the relationship to the diameter of the reflector in the range of 0.5 to 1.5 takes place was theoretically investigated. Thus, it was shown that the effect of shading on all directional characteristics is the less than the longer-focused is the reflector. The minimum level of side lobes is in the case of short-focused reflector


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45.  
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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46.  Compromising emanations: overview and system analysis
N.N. Gorobets, A.V. Trivaylo
compromising emanations, near-field-zone, electromagnetic, radiation, time domain
Vestnik KhNU 883 Pages. 83-88

The problem of compromising radiation of spurious signals in the near, intermediate and far zones of observation in time domain are considered. The Compromising emanation system analysis for finding spurious radiation is proposed. The goal of the given approach is to speed the development of technical protection of information. In approximation of the given current distribution it has been suggested a solution considering the influence of the near-field effects upon directional characteristics of spurious signals radiation. The application of the new method allows us to investigate compromising of technical means in time and frequency domain.


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