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. Multifunctional measuring platform for investigations parameters of metaldielectric structures V.A. Katrich, D.V. Mayboroda, S.A. Pogarsky, I.I. Saprykin automation complex, Dielectric image guide, energetic characteristics Vestnik KhNU ¹712 Pages. 2124
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. Scattering electromagnetic waves by coupling aperture of electrodynamic volumes in presence of finite sizes impedance body M.V. Nesterenko impedance vibrator, narrow slot, Distributed surface impedance, rectangular waveguide Vestnik KhNU ¹712 Pages. 4751
Systems of integraldifferential equations concerning surface equivalent magnetic and electrical currents which are excited with impressed sources of electromagnetic field in the coupling aperture of electrodynamic volumes and in the finite sizes impedance body have been obtained. The approximate analytical solution of the equations system for the narrow transverse slot in the broad wall of rectangular waveguide with the thin impedance vibrator was represented. Also theoretical and experimental graphs of electrodynamic characteristics of such structure in dependence on the wavelength in the base oscillations band the waveguide was represented
5. Application of the digital holographic interference microscope for investigation of human red blood cells 3D morphology T.V. Tishko, V.P. Titar, D.N. Tishko Digital holographic interference microscope, erythrocyte, morphology, sphericity coefficient, Diagnostics, microobject Vestnik KhNU ¹712 Pages. 5255
Results on the digital holographic interference microscope for 3D imaging of native blood erythrocytes are presented. Blood samples of healthy people and patients with different pathologies were used. Three basic morphology kinds of blood erythrocytes were detected. A sphericity coefficient was used as quantitative characteristics of blood erythrocytes morphology. It is shown that, blood erythrocytes 3D morphology is very important diagnostics characteristics in medical practice. The digital holographic interference microscope is an effective device for the purposes of medical diagnostics
6. 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.
7. Absorption of electromagnetic energy of dipole antenna of double layer dielectric sphere V.V. Radchenko wave absorption, Double layer dielectric sphere, perfectly conducting spherical screen, radial dielectric dipole, Dual series equations, method of analytical regularization Vestnik KhNU ¹712 Pages. 6266
Considered the problem of electromagnetic energy absorption by double layer sphere, which the simplified model of human head protected by the helmet with the dipole antenna. This investigation is interesting due to control of energy absorption in sensible parts of human head tissues. The problem is solved by method analytical regularization, which reduces the problem to the system of linear equations of Fredholm second kind which provides guaranteed convergence. Basic absorption characteristics are obtained and comparison of protection effectiveness for different sizes helmets are made
8. The influence of the inner chanal of a periodic irisloaded circular waveguide concerning its eigenmode mutual transformations He Shi, S.K. Katenev, S.N. Shulga Dispersion, Brillouin diagram, mode transformation Vestnik KhNU ¹712 Pages. 8083
The mutual eigenmode transformations are considered of a periodic irisloaded 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 ¹712 Pages. 8490
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 closedform 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. 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
11. On the directive gain of the selffocusing antenna Ya.S. Shifrin Directive gain, selffocusing antenna, inhomogeneities, structure function Vestnik KhNU ¹756 Pages. 1117
The influence of the atmospheric inhomogeneities on the directive gain of the selffocusing antenna array (SFAA) at description of the atmosphere by the theory of the localisotropic 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. Onedipole inverse problem of magnetostatics for reconstruction of hearttorso electric activity from magnetocardiography measurements Bagatskaya O., Butrym A., Durneva Yu., Shulga S. Do not determinated Vestnik KhNU ¹756 Pages. 4750
Do not determinated
13. INFLUENCE of ENVIRONMENT ON the FIELD, SCATTERING ON the LATTICE WITH LAYER, AT ANY FALL of the WAVE A.I. Adonina, V.B. Khokh lattice, environment, Dielectric, a stream of capacity, method of RimanHilbert problem Vestnik KhNU ¹756 Pages. 5156
The decision of a task in view is carried out for Å and Í the fields appropriate to two subsystems on which the system of the equations of the Maxwell for environments is divided. Integrated characteristics of a field are determined from the decision of systems of the linear algebraic equations received by a method of method of RimanHilbert problem , for a case when the smallest parameter decreases in inverse proportion to a square n>infinity. Programs (fort) with construction of diagrams are made. The analysis of the diagrams in part given in work, allows to establish influence of parameters of structure and corners of fall of a wave on anomalies in an absentminded field for each concrete case
14. DESTRUCTION OF PULSE TRAINS IN WEAKLY NONLINEAR OSCILLATOR D.D. Vavriv chaos, Dynamical systems, train pulses, quasi linear oscillator Vestnik KhNU ¹756 Pages. 7178
A study has been carried out on the transition of train of pulses via a weakly nonlinear oscillator. Conditions of destruction of such trains as a result of appearance of chaotic instabilities have been analyzed. Analytically conditions of the appearance of chaotic instabilities have been determined by using the method of secondary averaging.
15. GAUSSIAN EXPANSIONS FOR RADIATION PATTERN OF AN OPENENDED LINE WITH IMPEDANCE BORDERS A.P. Udovenko aperture distribution, impedance border, orthogonal functions, Diffraction integral, feed Vestnik KhNU ¹756 Pages. 8790
Nearfield and farfield twoparameter expansions in terms of LaguerreGaussian orthogonal basis functions are proposed, which take into account the effect of impedance feed borders. The expansions enable the feed characteristics on a base of lines with impedance borders to be calculated in wide frequency region. Radiation intensity distributions for the openended twolayer metalshielded dielectric waveguide in a nonresonance regions of surface impedance varying, relative errors of expansion truncations, comparison with experimental data are presented
16. Al_{0,3}Ga_{0,7}As/GaAs cathode transfer electron diode's efficiency O.V. Botsula Prokhorov E.D, A.V. Dydchenko Doping, cathode contact, tunnelling, negative differential conductivity, oscillation efficiency Vestnik KhNU ¹756 Pages. 97100
The results of analyse efficiency of GaAs/ Al0,3Ga0,7As/GaAs GaAs/ Al0,3Ga0,7As/GaAs / GaAs cathode transfer electron diode are present. The space charge model are used. There are two region of negative differential conductivity of current  voltage characteristic are shown . The condition lead to oscillation due both region and oscillation efficiency have been determined.
17. Influence of impact ionization on efficiency of rscadiodes operation on basis of InN, GaN, AIN D.V. Pavlenko, E.D. Prokhorov nitrides, RSCA oscillators, oscillating efficiency, Drift velocity Vestnik KhNU ¹756 Pages. 109112
The impact ionisation in RSCA diodes is considered on the basis of nitrides InN, GaN, AIN. Possible overvoltage on diodes and possible efficiency of generation are analyzed. It is shown, that at development of a impact ionisation in RSCA diodes in correspondence with the diffusion theory the considered materials are perspective for RSCA diodes for operation in centimeter and millimeter wavebands (voltage over threshold 3 ... 5 at efficiency up to 11 ... 13 %)
18. THE H_{10} WAVE SCATTARING BY THE THIN VARIABLE RADIUS IMPEDANCE VIBRATOR IN A Nesterenko, E.Y. Belogurov, V.A. Katrich, V.I Kijko impedance vibrator, biconical vibrator, Distributed surface impedance, rectangular waveguide, the method of induced electromotive forces Vestnik KhNU ¹806 Pages. 1417
The problem of the fundamental wave scattering by the thin variable radius impedance vibrator arbitrary situated in a rectangular waveguide was solved. Calculations were carried out and energetic characteristics of such structures were plotted
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19. 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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20. The influence of a dispersion and losses to the interaction of impulse signal with the model of the biological tissues O.N. Zheryobkina, O.V. Kazanskiy impulse signal, a biological tissue, time domain, flatlayer dielectric, Dispersion Vestnik KhNU ¹806 Pages. 4043
In this paper the interaction of the impulse signal with biological tissues on an example of the flatlayer dielectric that models consecutive layers a skin, fat, muscle tissue is investigated. In this model, it is taken into account dispersion of the dielectric permeability and losses in a medium. The calculation program is received in result. It accounts the spacetime characteristics of the reflected and past signals for layers of the flatlayer dielectric with parameters of biological tissues. Influence of values of the dielectric permeability and angle of incidence on the characteristics of past and scattered signals also is considered.
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21. Thermo equilibrium and differential capacity of p^{+}n junction N.A. Shekhovtsov p^{+} n junction, Distribution of potential Vestnik KhNU ¹806 Pages. 4853
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 nregion 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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22. Thermo equilibrium state of p^{+}p junction N.A. Shekhovtsov p^{+}p junction, Distribution of potential Vestnik KhNU ¹806 Pages. 5458
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 unknown 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 ionacceptors in pregion was obtained.
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23. HARMONIC GENERATION BY IMPACT IONIZATION IN CaN LSA DIOD O.V. Botsula, D.V. Pavlenko, E.D. Prokhorov LSA diodes, generation efficiency, nitrides, Drift velocity, harmonics Vestnik KhNU ¹806 Pages. 6569
In this work an impact ionization in LSA diodes on basis of GaN is considered. Analytical calculation of typical times of passing of a number of the physical processes determining properties of the oscillator, and limitings imposed by them on frequency properties of the diode is submitted. It is shown, that at developing impact ionization in LSA diodes, according to the diffusive theory, the considered compounds are perspective for manufacturing LSA diodes for work in sm and mm  ranges (electrical pressure over threshold 3 … 5 times, at an efficiency up to 11 … 13 %). The results of calculation of efficiency of oscillators on basis of GaN LSA diodes are given at their work in modes on a base frequency and at a harmonic generation.
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24. 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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25. 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, threedimensional images, vacuumarc method, thin AlN films Vestnik KhNU ¹806 Pages. 99102
For the first time the digital holographic interference microscope (DHIM) was used for investigation of thin films on transparent substrates. Threedimensional images of AlN of thin films, deposited on acryl substrates by the vacuumarc 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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26. Dispersive characteristics of magnetoplasma waves in the rectangular wave guide with InSb O.A. Zamuraev, O.O. Puzanov, A.S. Tishchenko magnetoplasma wave, semiconductor plasma, Dispersive characteristics, nitric temperature Vestnik KhNU ¹834 Pages. 37
Frequency dependence of characteristics of magnetoplasma waves in the rectangular wave guide, containing longitudinal and crosssection  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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27. Subterahertz diffraction radiation on the BWO frequency harmonics in the parametrical tworegimes electron device E.N.Odarenko, A.A.Shmat’ko, P.V. Yudintcev Diffraction radiation, SmithPurcell effect, subterahertz waves, beamwave interaction, nonlinear processes Vestnik KhNU ¹834 Pages. 1317
Diffraction radiation nonlinear theory that takes into account tworegimes interaction – selfconsistent regimes of the BWO and GDI on the BWO frequency harmonics is developed. The existence of the BWO generation regime on the first harmonic and parametric type diffraction radiation amplification regime on the BWO frequency harmonics is shown on the base of the selfconsistent equations set numerical solution. Ranges of the task parameters values that correspond to tworegimes interaction are defined
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28. 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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29. 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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30. Frequency multiplication at impact ionization in GaNdiodes Î. V. Botsula, D. V. Pavlenko, E. D. Prokhorov the GaN diode, coefficient conversion transducing, Drift velocity, harmonics Vestnik KhNU ¹834 Pages. 100103
The frequency multiplication at impact ionization in transfer electron GaN diodes nave been considered. The coefficient conversion transducing increase if impact ionization in GaN diodes takes place have been demonstrated. For example, coefficient conversion transducing in second harmonic arrive at 40 %.
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31. Global Sensitivity analysis of the dipole matrix element according to variation of parameters of the indium surface segregation in ingan/gan quantum well M.V. Klymenko indium surface segregation, semiconductor nitrides, piezoelectric polarization, Dipole matrix element, global sensitivity analysis Vestnik KhNU ¹853 Pages. 814
In this paper, influence of the indium surface segregation on dipole matrix element for InGaN/GaN heterostructure is under investigation. The global sensitivity analysis has been applied for quantitative estimation of the indium surface segregation effect at each interface of the quantum well. Together with the indium surface segregation, the piezoelectric effects are considered. It has been shown that joint action of the piezoelectric fields and the indium surface segregation leads to changes in the selection rules for optical transitions. Results give the method to apply the optical spectroscopy for observation of the indium surface segregation
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32. Oscillation efficiency of TED diodes on the basis of nitrides E. D. Prokhorov, O. V. Botsula, A. N. Zabazhan AlN, GaN, InNdiodes, Drift speed, oscillation efficiency Vestnik KhNU ¹853 Pages. 1521
Oscillation efficiency of intervalley transfer electrons diodes on the basis of nitrides (InN, GaN, AlN) is considered. Electric fields at peak oscillation efficiency are determined. The results have been compared to results for GaAs. The account of floatable potential in connections InGaN improves their power characteristics in comparison with power characteristics of these connections without taking into account floatable potential, maximal efficiency In_{0.8 }Ga _{0.2N and In0.5Ga0.5N diodes to compare to InN diodes on 30 % is higher (22 % to compare to 16,43 %) but at more high tensions of an electric field. The maximal oscillation efficiency is observed at higher electric fields than GaAs ( from 250 êV/sm for InN to 1000 kV/sm for AlN)}
33. Inner partial mutual admittance of two overlopping longitudinal slots in a rectangular waveguide with dielectric layer parallel to narrow walls A.A.Lyakhovsky, L.P.Yatsuk, A.F.Lyakhovsky , layer, Dielectric, slot, admittance, scattering parameters Vestnik KhNU ¹853 Pages. 2227
The expression for the partial inner mutual admittance of two longitudinal slots overlapping along waveguide longitudinal axis is obtained. The slots are cut in a broad wall of a rectangular waveguide filled with threelayered dielectric. The excitation problem is solved with the modified eigen waves method. As eigen waves of the LE and LM modes are chosen. The field in the source region includes the potential functions as well. Dependences of inner mutual admittance and scattering parameters on distance between two slots and frequency are investigated. The system scattering parameters calculated are in a good agreement with experimental data
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34. 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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35. Asymptotic method of the solution of diffraction problem on the convex impedance cylinder, excited by the string of the electric current V.I. Vyunnik, A.A, Zvyagintsev Diffraction, asymptotic method, interpolation, convex impedance cilinder Vestnik KhNU ¹853 Pages. 6470
In the work considered the problem of diffraction electromagnetic waves on the convex impedance cylinder exited by string of the electric current, located near to its surface. The method asymptotic theories of the diffraction, offered by Fok is used. Are received asymptotic interpolation formulas for calculation radar cross section of the system string the current  cylinder, for a case of circular and elliptic impedance cylinders. The received formulas are suitable for calculations both in shadow and in lighted areas. It is shown, that these formulas can be distributed on a case of the any convex impedance cylinder with variable curvature
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36. 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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37. HF ionosonde signal focusing by traveling ionospheric disturbances Yu. B. Milovanov, V. F. Pushin, O. F. Tyrnov traveling ionospheric disturbances, signal amplitude variations, Doppler frequency shift, focusing factor, computer simulation Vestnik KhNU ¹853 Pages. 8894
HF signal focusing due to linear and nonlinear wave disturbances occurring during monostatic ionospheric sounding is discussed. A technique is developed for estimating signal amplitude variation due to focusing based on beating amplitude measurements during significant Doppler frequency shift events. The intercomparison of measured and modeled variations in beating amplitudes, the focusing index, and Doppler frequency shift show a qualitative agreement. The simultaneous analysis of variations in the beating amplitude and the Doppler frequency shift makes the interpretation of measurements more definite, e.g., it permits the isolation of large scale disturbances traveling at approximately 1 km/s
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38. 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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39. Longitudinal slot in a rectangular waveguide with dielectric layer parallel to wide walls A.A.Liakhovskyi slot, microwaves, waveguide, Dielectric, admittance, scattering parameters. Vestnik KhNU ¹883 Pages. 5966
The longitudinal slot is cut in wide wall of rectangular waveguide with threelayer dielectric filling which parallel to wide wall is considered. The excitation problem is solved with modified eigen waves method. As eigen waves of the LM and LE modes ar
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40. Dielectric permittivity profile reconstruction by frequency probing problem for a planelayered media with regard to dispersion Batrakov D.O., Simachov O.A. plane layered media, Dispersion, inverse problem, Dielectric permittivity Vestnik KhNU ¹883 Pages. 4549
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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41. 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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42. Signal scattering on the meteor trail Kharchenko H.V. signal scattering, meteor trail, Diffraction oscillations, electron density, plasma collective interaction, impulse response. Vestnik KhNU ¹966 Pages. 9096
A generalized model of the radiosignal scattering on the meteor trail is proposed. The model allows to take into account the process of formation and development of the meteor trail, and to calculate the scattered signal power change without sharing the meteor trails on underdense and overdense. As input parameters of the model used the physical parameters of the meteoroid  the mass and velocity, which determine the ionization of the plasma formation, as well as the location and orientation of the meteor trail. In the derivation of the analytical relations taken into account the presence of the plasma sheath surrounding the 'metal cylinder' and the collective interactions in the plasma. In the paper shown that the results of calculations are in good agreement with observations.
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43. 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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44.
radioholography, multiposition spatiallycoherent system, Dynamic conflict situation Vestnik KhNU ¹966 Pages. 7276
Possibility of creation of the radioholographic informative system is shown for the decision of problem tasks of modern and perspective radiolocation and construction on its example of system theory of radiolocation. The decision of problem tasks of radiolocation brings a necessity over to determination of ways of its development, and a necessity of decision of basic problem task of radiolocation systems engineering is developments system the theory of radiolocation  results in determination of ways of development of formal language for description of the state and conduct of the difficult system. They, in same queue, result in the necessity of increase of system indexes of quality of the system, especially at the supervision of stream of objects in the conditions of strong counteraction, and to the necessity of creation of the most informative system of new generation. The technical look of such system is examined.
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45. 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 current regions due to impact ionization that is nonlinearity and lead to transparent frequency. If impact ionization takes place, frequency transformation factor increases and reaches, for example, 40 % for second harmonic have being showed. The frequency transformation factor increases for second and third harmonic if first harmonic voltage amplitude is several threshold voltage if compare with frequency transformation factor for all nitride compounds.
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46. layered media, Dispersion, inverse problem, Dielectric permittivity. Vestnik KhNU ¹883 Pages. 4549
In the present paper the problem of dielectric permittivity profile reconstruction with regard to dispersion is discussed. The nature of the dispersion function is assumed to be known and unknown functions are real and imaginary parts of dielectric permittivity. Frequency is used as an informative parameter. It is assumed that the layered medium is laying on a substrate with known dielectric permittivity and permeability. The iterative method reducing the problem of reconstruction to the functional minimization problem is used. Within the scope of this method the inverse problem for of dielectric permittivity profile with a conducting medium dispersion is solved. The algorithm and numerical results are given.
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47. Diffraction electromagnetic waves, chiral structure, polarization properties on frequency Vestnik KhNU ¹883 Pages. 5458
In given paper the diffraction of electromagnetic waves on volume grid is investigated experimentally. The grid consists of rectangular elements. Two planes of twodimensional periodic rectangular metallic string elements located on both dielectric surfaces and connected by cylindrical conductors. The measurements of dependence of grid transmission index on frequency and polarization are carried out. The measurements were made in frequency range 2638,8 GHz. The grid was irradiated by quasiplane wave with incident on the normal to the surface of the grid.
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48. slot, microwaves, waveguide, Dielectric, admittance, scattering parameters Vestnik KhNU ¹883 Pages. 5966
The problem of a longitudinal slot radiation is cut in wide wall of rectangular waveguide with threelayer dielectric filling which parallel to wide wall of a waveguide was solved. The excitation problem is solved with modified eigen waves method. As eigen waves of the LM and LE modes are chosen. The field in the source region includes the potential functions as well. The scattering parameters and resonance properties of slot are investigated. The scattering parameters calculated are in a good agreement with experimental data.
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49.
antenna array, horizontal polarization, Double slots, slowing system. Vestnik KhNU ¹927 Pages. 5458
Energetic and directional characteristics of an antenna array (AA) with single transversal slots and double ones cut in a rectangular waveguide, partially filled with dielectric are investigated. In the case of single transversal slots and double transversal slots a dielectric layer is parallel to broad walls of the waveguide. It was shown the possibility to construct an AA with double transversal slots having the pattern without diffraction lobes and high level of radiation power in the wide frequency band.
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50.
slot, waveguide, Dielectric, admittance, scattering parameters, slotwaveguide array. Vestnik KhNU ¹927 Pages. 5964
The scattering problem of a longitudinal slot system is cut in wide wall of rectangular waveguide with threelayer dielectric filling which parallel to wide wall of a waveguide was solved. The scattering parameters and gain of linear slottedwaveguide array are investigated in range of frequency. The gain optimization and synthesis of linear slottedwaveguide array were carried out using a genetic algorithm. The obtained gain weakly depends from frequency.
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51.
GaAs diodes, Drift speed, lag, coefficient frequency conversion, maximum frequencies. Vestnik KhNU ¹927 Pages. 1114
Coefficient frequency conversion (KFC) diodes with intervalley transfer of electrons based on GaAs in a wide range of frequencies is investigated. It is shown that the threshold voltages of the KFC in mobility 8000 sm2/(V·s) (GaAs) more than the KFC in 1000 sm2/(V·s) mobility (without NDC) in 5 times. At the further increase voltages in the mobility ratio of KFC 8000 sm2/(V·s) to KFC for 1000 sm2/(V·s) mobility decreases (at 10  12 kV/cm is about 2, at 20  30 kV/cm ratio KFC close to unity). Take into account the inertia of the redistribution of electrons between the valleys of the conduction band of GaAs. It is shown that the transformation frequency conductivity GaAs diodes is possible at frequencies exceeding the maximum frequency of generation in the diode mode of a uniform field.
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52.
plane dielectric waveguide, inverted dielectric waveguide, Fourier transformation, Fredholm integral equation, Dispersion equation. Vestnik KhNU ¹927 Pages. 7884
The eigenvawes problem of inverted dielectric waveguide is considered. The crosssection of waveguide is divided into partial domains in such way that the field in each domain is represented as a superposition of eigenwaves of a plane dielectric waveguide. Using the equality conditions of tangential components of electric and magnetic fields at the interface of domains two Fredholm integral equations of the second kind relatively waves amplitudes are obtained. The symmetric and asymmetric waves are considered. The dependencies of the propagation constant versus wave number and field distribution in the waveguide are presented.
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53.
waveletanalysis, continuous wavelet transform, Dynamic energogram, space radio physics, powerful nonstationary disturbance sources. Vestnik KhNU ¹927 Pages. 96102
Development and improvement of methods of timefrequency analysis of signals with continuous wavelet transform usage were proposed. The new method consists in the simultaneous analysis of wavelet spectrum and dynamic energograms of the continuous wavelet transform. Using the example of analysis of real nonstationary, nonlinear and ultra wideband signals and processes in space radio physics problems, in particular, using the analysis of effects, caused by the powerful, nonstationary action, the dynamic energogram method effectiveness was shown.
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54.
laser, optical radiation, intensity, Distribution, receiver, Direct problem, inverse problem. Vestnik KhNU ¹927 Pages. 3135
In this paper has been considered the method of the measurement of the intensity distribution in the beam of optical radiation and the algorithm of processing of a signal from the receiver. The method is using the knife attenuator of the special shape. The power of the reflected radiation on knife was measured by using detector of photoelectric. The algorithm and program for handling of the signal from receiver are developed. The influence of errors in the measurement signal from the receiver on the results of calculations has been researched. The experiment has confirmed the serviceability of the method and the possible of their use in practice.
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55.
DKDP single crystals, Dc electrical conductivity, concentration of Ldefects, gamma irradiation, first order kinetics. Vestnik KhNU ¹927 Pages. 2230
The dependence of electrical dc conductivity of KD2PO4 (DKDP) single crystals on the dose of ?irradiation is investigated. The conductivity is found to decrease exponentially in a dosage range of 3.0 102÷2.8 104 Gy. The temperature dependences of the conductivity are described by the exponential law. The preexponential factor and activation energy values of conductivity are determined for the crystals irradiated with various doses. Analysis of the dose and temperature dependences shows that the radiationinduced decrease of the conductivity is associated with the decrease of Ldefect concentration in the crystal. The concentration changes in accordance with the law of first order kinetics. Possible mechanisms of the Ldefect concentration changes under gamma irradiation of crystals are discussed.
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