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 ¹712 Pages. 816
The relationship between complex dielectric permittivity of twocomponent 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 ¹712 Pages. 1720
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, TEMwave, radiation Vestnik KhNU ¹712 Pages. 4246
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 TEMwave 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 dualmode circular waveguide excited by dominant and higherorder modes simultaneously A.V. Shishkova, N.N. Gorobets microwaves, multimode waveguide, diffraction, higherorder modes, Weinstein rigorous technique, WienerHopf technique, radiation pattern. Vestnik KhNU ¹712 Pages. 5661
On the basis of Weinstein rigorous solution to the problem of electromagnetic mode diffraction at an openended circular waveguide the characteristics of radiation from multimode waveguides excited by H_{11} dominant mode and. higherorder modes (E_{01}, and H_{01}) 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 higherorder 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 ¹712 Pages. 7175
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 ¹712 Pages. 9599
Problem of harmonic electromagnetic wave diffraction on a resistive cone with longitudinal slots is considered. The boundary problem solution uses the KontorovichLebedev integral transform and a semiinversion 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 ¹712 Pages. 127131
Based on the model considerations it was shown that irradiation of liquids containing gas inclusions with electromagnetic fields of "slowlyconvective" 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 middleaperture SPHERICAL antenna I.V. Baryshev, N.N. Gorobets, N.I. Matjuhin radioholography, multiitem coherent systems, middleaperture spherical and ring antennas, range of direct visibility Vestnik KhNU ¹756 Pages. 1821
Basic opportunities of creation of perspective radioholographic information system which is capable to carry out full radartracking 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 middleaperture SPHERICAL antenna I.V. Baryshev, N.N. Gorobets, N.I. Matjuhin radioholography, multiitem coherent systems, middleaperture spherical and ring antennas, range of direct visibility Vestnik KhNU ¹756 Pages. 2226
Basic opportunities of creation of perspective radioholographic information system which is capable to carry out full radartracking 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 ¹756 Pages. 2732
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 ¹756 Pages. 4246
By using the approach that is based on applying the Kontorovichlebedev integral transforms method and a semiinversion 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 L_{2} FOR 2D SCREENS A.G. Tyzhnenko, Y.V. Ryeznik testing, reference solution, moment's method, 2D screens Vestnik KhNU ¹756 Pages. 6570
The scattering amplitude error estimation problem for practically used MoM solutions in L_{2} function space for scattering from 2D screens is addressed. To this end, a rigorous Galerkin solution in L_{2} 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 illconditioning connected with high mesh density for any MoM solution to the EFIE in L_{2}. 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, À.N. Katunin, Ê.V. Sadovy, S.I. Shmatkov , speckle – interferometrician, anemometrician, speckle – painting, lightreflecting coverage Vestnik KhNU ¹756 Pages. 118122
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 lightreflecting coverage. Is dependence of increase of border frequency of signal’s 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 HIGHorder 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 highorder transverse modes, an amplitude filter, Fourier optics Vestnik KhNU ¹756 Pages. 123131
The method of the space Fourierfiltration for selective excitation of separated highorder 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 amplitudestepped mirrors for shaping the highorder 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 ¹756 Pages. 132138
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 ¹756 Pages. 139143
The biologically active points (BAP) show an increase in size due to an increase in size of air bubbles at nearmembrane 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 ¹806 Pages. 37
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 axialsymmetric 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 ¹806 Pages. 813
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 miñrowaves, antennas, pattern, Frenel zones Vestnik KhNU ¹806 Pages. 2932
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 shortrange, medial and longrange bands for different frequency range are received and analyzed. By results of experiments intensity, a corner, radius for longrange and shortrange 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 ¹806 Pages. 3339
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 ¹806 Pages. 7074
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, dualfrequency Doppler shift measurements, planetary waves Vestnik KhNU ¹806 Pages. 8286
Experimental study of the latitudinal and diurnal variations in the total electron content over Eastern Europe are present. The dualfrequency Doppler shift measurements from navigation satellites and incoherent scatter radar (ISR) data are used The ISR data were collected near Kharkiv city (49.6^{o}N, 36.6^{o}E), and the dualfrequency 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 (49.6^{o}N, 36.3^{o}E). The calculated total electron content maps span the 35^{o} – 65^{o}N geographic latitude range and the 24hour 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 50^{o}N geographic latitude in total electron content. The results obtained also indicate that tidal and planetaryscale 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 highorder modes in the waveguide resonator by means a phaseshifting 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 highorder transverse modes, a phase filter, Fourier optics, selection Vestnik KhNU ¹806 Pages. 8791
The method of the space Fourierfiltration for selective excitation of separated highorder 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 phaseshifting mirrors for shaping of the highorder 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 ¹806 Pages. 103106
Using an NMR technique the volume growth of the free ("bubble") air contained in water caused by lowintense 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 lowintense waves.
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25. Fields of the rectangular loop antanna in nearfield zone N.N. Gorobets, À.V. Trivaylo electromagnetic waves, radiation, nearfield zone, Hertz vector, traveling wave antenna, loop antenna Vestnik KhNU ¹834 Pages. 1824
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 extraatmospheric researches A.F. Sorokin, A.A. Sorokin, N.N. Gorobets, O.V. Sokolova radar, a, microwaves, space garbage Vestnik KhNU ¹834 Pages. 2530
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 largesized aerials to a ADU  1000 and P400 such radar at length of a wave ~ 30 cm at heights ~ 10^{5} ì finds out objects with the minimal sizes ~ 0,7 cm. On a disk of the Sun the spatial sanction ~ 10^{3} 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 ¹834 Pages. 3136
A new method identification of target’s 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. Farfield 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 ¹834 Pages. 6876
On the basis of Hertz potentials in Kirchhoff approximation the amplitude and phase radiation characteristics of openended rectangular waveguide excited by TE_{10} 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 farfield 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 farfield 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 ¹834 Pages. 7784
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 ¹834 Pages. 8994
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(N1), 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 physicalmathematical level A. G. Tyzhnenko, E. V. Ryeznik bit, stochastic signals, safe communication, hard drive protection Vestnik KhNU ¹834 Pages. 108113
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 apertureillumination law on nearfield characteristics of aperture antennas E.E. Ovsyannikova, A.V. Shishkova, N.N. Gorobets electromagnetic waves, reactive fields, aperture radiators, Kirchhoff technique, nearfield, farfield, amplitude distributions, phase characteristics, amplitude characteristics, reactive radiation power Vestnik KhNU ¹853 Pages. 2836
On the basis of Hertz potentials the investigation of nearfield 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 nearfield region have been carried out. The analysis of the criteria for estimation of nearfield 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 ¹853 Pages. 3744
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, planelayered media, thickness measurements Vestnik KhNU ¹853 Pages. 7176
In the present paper the algorithm of processing of the pulse signals reflected from planelayered 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 ¹853 Pages. 7783
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 crystalbased 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 lowintensity 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 ¹853 Pages. 95100
When a medium is irradiated by laser pulses, sound waves are excited in this medium, i.e., the wellknown 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 (thermooptical 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 ¹883 Pages. 3034
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 ¹883 Pages. 811
In paper a theoretical analysis of quantum efficiency of resonance InGaAs/GaAs Pin 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 ¹883 Pages. 37
The mechanism of the accumulation of gas in the galactic objects submerged in the largescale 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, À.V. Trivaylo compromising emanations, nearfieldzone, electromagnetic, radiation, time domain Vestnik KhNU ¹883 Pages. 8388
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 nearfield 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 nonorthogonal linearly polarized basis Gorobets N.N., Chekalin , Chekalina G.N. ålectromagnetic wave, electric field strength,timedistance curve, harmonic basis, the expansion of the harmonic, the polarization model
Vestnik KhNU ¹966 Pages. 5055
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. Ðåøåò÷àòûé ïðèåìíèê äëÿ èçìåðåíèé õàðàêòåðèñòèê ëàçåðíîãî èçëó÷åíèÿ Lizogubenko S.V., Kokodiy N.G. scattering pattern, diameter of the particles, scattering, brightness of the light spot, beam intensity Vestnik KhNU ¹966 Pages. 912
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 ¹966 Pages. 38
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 singlereflector antenna by focal module on directional characteristics Gorobets N.N., Kiyko V.I. microwaves, reflector antennas, reflector shading, directional characteristics Vestnik KhNU ¹966 Pages. 97102
The effect of shading of the radiating aperture singlereflector 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 longerfocused is the reflector. The minimum level of side lobes is in the case of shortfocused reflector
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45. magnetocardiography, gradiometer, current dipole, sensitivity, Hessian Vestnik KhNU ¹883 Pages. 2529
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, nearfieldzone, electromagnetic, radiation, time domain Vestnik KhNU ¹883 Pages. 8388
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 nearfield 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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