1. 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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2. The exitation H_{p0} waveguide wave of the T–brunching with matching resonator V. N. Mizernik, A. A. Shmat'ko a branching of the waveguides, matching nouniformity, connection area, system of the linear algebraic equations Vestnik KhNU ¹834 Pages. 812
In strong electrodynamics statement the problem of excitation H_{p0} waveguide a wave by of the Tbranching with two types matching resonator is solved: otherworld and through passage. Results of calculation of amplitudefrequency characteristics of the module of factor of reflection for various parities between length of a wave and the geometrical sizes of structure are presented. Areas of value of parameters of the full coordination of wave guides are certain
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3. 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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4. 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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5. 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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6. 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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7. Earth profile plotting using pulse radar with scanning antenna array A. S. Kutsenko, Î. V. Kazansky, N. N. Kolchigin pulse radar, antenna array, radar image Vestnik KhNU ¹834 Pages. 3741
This paper is devoted to development of radar signal processing technique which allows one to reconstruct earth profile and reveal and identify manmadc objects which arc situated on underlaying surface. The technique of signal processing and image construction is based on measuring of directional characteristics of the scene being investigated. Modeling of radar activity has been performed; radar images of some simple scatterers have been obtained. Possibility of using the technique for scene profile reconstruction and revealing of manmade objects situated on it has been shown
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8. Structure and the contents of the hypertext databaseof problems of remote sounding of the ground from space L.M.Atroshenko, N.N.Gorobets, L.P.Safronova, S.A.Smirnov ðroblems of remote sensing, a database Vestnik KhNU ¹834 Pages. 4251
The principle of construction and filling of a hypertext database of problems of remote sensing of the Earth from Space including more 4000 problems RSE are described. The approach to an optimum choice of a sensor control is illustrated by the examples of use of active and passive sounding in a radiorange
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9. Features of the calculation of Focktype integrals V.I. Vyunnik, A.A, Zvyagintsev Focktype integrals, numerical integration, error estimate Vestnik KhNU ¹834 Pages. 5262
Calculation of Focktype integrals, used at the solutions of the diffraction problems on convex bodies is considered. The method of calculation of this integrals is described, and the estimation of their convergence is given. Range of values of the complex parameter, describing a surface impedance, for which the given method is applicable is determined. The estimation of the error of calculation is carried out
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10. Radiation of short pulses from the open end of waveguide O.M. Dumin, O.O. Dumina, V.O. Katrich, Zheng Yu transient field, modal basis method, evolutionary equations, impulse field irradiation Vestnik KhNU ¹834 Pages. 6367
The problem of transient electromagnetic field radiation from the open end of waveguide is solved in time domain by the analytical and direct numeral methods. The problem of impulse signal propagation in regular waveguide is converted to the finding of transient wave propagation operator by modal basis method. The application of the operator for the obtaining of time form of signal both for the time change in positive and in the negative direction permits to seek an arbitrary time dependence of field amplitude in any point of waveguide taking into account distortions due to wave dispersion. The correction of diffraction distortions of time form of wave and forming the short probe impulse on the waveguide aperture by the excitation of waveguide in the given crosssection by field with the previously calculated time dependence are considered . Numerical simulation of short impulse irradiation of layered medium with losses is carried out
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11. 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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12. 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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13. Near electromagnetic field of combined waveguideslot radiators in matter S.L. Berdnik, V.A. Katrich, M.V. Nesterenko, S.V. Pshenichnaya rectangular waveguide, waveguideslot radiator, material medium, hyperthermia, Galerkin's method Vestnik KhNU ¹834 Pages. 8588
The problem about the electromagnetic waves radiation into the homogeneous isotropic medium by the system of combined waveguideslot radiators in the broad wall of a rectangular waveguide has been solved in a rigorous selfconsistent formulation. The spatial distribution of the near field intensity in the halfinfinite material medium with the electrophysical parameters, corresponding to some man's tissues, has been investigated
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14. 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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15. Features of radiation defect formation in kdp crystals under different kinds of irradiation A.N. Levchenko KDP single crystal, UV, ionizing irradiation, radiation centers, ESR Vestnik KhNU ¹834 Pages. 9599
Formation processes of different types of radiation paramagnetic centers in potassium dihydrogen phosphate (KDP) single crystals under ultraviolet (UV), gamma, electron, neutron and proton kinds of irradiation have been investigated with the help of electron spin resonance (ESR) method. The dose dependencies of the relative concentration of the impurity electron centers containing arsenic ions and holelike centers with the hole localized on the porbit of oxygen ion have been measured. The comparison of the effects of the different kinds of irradiation on the radiation paramagnetic defect formation processes has been carried out
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16. 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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17. Cathode static domen in transfer electron devise Î. V. Botsula, D.V. Pavlenko, E.D. Prokhorov static domen, velocity – field characteristic, electric field strange Vestnik KhNU ¹834 Pages. 104107
The diode in which static cathode domen and under certain conditions impact ionization takes place has being considered. Transit time effect and noise oscillations takes place under impact ionization. The volatge to be lead to electric field strange abow 200 êÂ/sm (for gomogenues velosity – field characteristic in ower dides) have been derermened
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18. 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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19. Pulse water insonification for laboratory research of electromagnetic wave propagation and dispersion in randomly inhomogeneous media in order to meet the conditions close to working ones V.B. Yuferov, A.N. Ponomarev, E.V. Mufel, A.N. Ozerov, I.V. Buravilov, V.N. Ishenko electromagnetic wave propagation, inhomogeneous medium, air bubbles in liquid, acoustic pulse pneumatic radiator Vestnik KhNU ¹834 Pages. 114119
The efficiency of pulse water insonification by pneumatic radiator is shown. Such radiator enables the formation above the water surface of hydrometcors and aerosols with a desired concentration. It is necessary for laboratory research of fluctuation phenomena of the electromagnetic wave propagation in randomly inhomogeneous media. The use of pneumatic radiator makes possible lo remove salt from the solution. This enables a certain degree of control over liquid permittivity
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20. Potential of a spherical segment which is placed within a spherical layer with circular aperture. V.A. Rezunenko electrostatics, spherical segment, layer, Fredholm integral equation Vestnik KhNU ¹834 Pages. 120126
The rigorous solution of an axially symmetrical electrostatics problem is obtained. The potential of an ideal spherical segment, which is placed within a spherical layer with circular aperture, is analyzed. We use the methods of regularization, separation and inversion of summarized equations, the method of residues in singular points of analytical functions, the methods of contour integrals and integral transformations. Fredholm integral equation of the second kind with a compact operator in Hilbert space L_{2} is obtained. The comparison with known results and limit variants is given. The effectiveness of the constructed algorithm is confirmed. Some generalizations of the problems are considered
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