Kharkov National University
V.N.Karazin
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1.  Millimeter wave rotational spectrum of the lower excited vibrational states of CH3CF2Cl
O.I. Baskakov, V.V. Ilyushin, E.A. Alekseev
molecule, Rotational spectrum, interacting states, Hamiltonian, HCFC-142b
Vestnik KhNU 712 Pages. 3-9

The millimeter rotational spectrum of CH3CF2CI has been investigated. The rotational, centrifugal distortion and quadrupole coupling parameters have been determined for the vibrational states with energies below 600 cm-1. Parameters of the ground and 111, 171, 181, 171181 and 111 states have been obtained for both chlorine isotopic species. In addition, the 1111, 182, 101, 161, 91 and 111181 vibrational states have been studied for CH3CF235C1 molecule. It was found the interaction between 101 and 161, and 91 and 111 181 couples. The transition frequencies calculated with the parameters obtained coincide with the measured ones within experimental uncertainties.



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

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



3.  Longitudinal slot radiators cut in circular waveguide
E.Y. Belogurov, V.A. Katrich, V.A. Lyaschenko
circular waveguide, axial slot, electromagnetic waves, Radiation, slot antennas
Vestnik KhNU 712 Pages. 37-41

Using method of magnetomotive forces investigations of behaviors of longitudinal slots that were cut in wall of the circular waveguide were carried out. Expressions of internal self-admittance and transfer conductance were de- rived. The possibility of creation of a tapered illumination that forms radiation pattern with low side lobes on long slot cut in circular waveguide was shown



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

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



5.  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 712 Pages. 47-51

Systems of integral-differential 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



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

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



7.  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 712 Pages. 62-66

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

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



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

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



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 712 Pages. 95-99

Problem of harmonic electromagnetic wave diffraction on a resistive cone with longitudinal slots is considered. The boundary problem solution uses the Kontorovich-Lebedev integral transform and a semi-inversion method. Analytical solutions are obtained for the cone with a lot of narrow slots and reactive impedance. Impedance and longitudinal slots effects on scattering field structure is studied



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

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



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

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



13.  Radioacoustic wind sounding of the atmosphere bo un dat y layer: history of the development and perspectives
Y. N. Ulyanov, V. I. Vetrov, N. G. Maksimova
Radioacoustic, wind, sounding, atmosphere, boundary layer, profile, adaptation
Vestnik KhNU 756 Pages. 27-32

The article is devoted to the potentialities of the method of radioacoustic sounding when monitoring the vertical structure of the wind in the atmosphere boundary layer (ABL). A review of methods for radioacoustic measurements of the horizontal wind velocity and direction is based on the developments of the authors and their experience in this field as well as on the world experience. It is emphasized that the radioacoustic method for sounding the wind in ABL is perspective, since for the RAS equipment, there are not characteristic neither high levels of the electromagnetic pollution of the environment like for radiolocation wind profilers - radars nor loss of the serviceability at ligh levels of the ambient acoustic noise like for acoustic wind profilers - sodars.



14.  ELECTROMAGNETIC WAVE SCATTERING FROM ANISOTROPIC INCLUSION IN RECTANGULAR SHORT-CIRCUIT WAVEGUIDE
N.P. Zhuck, V.I. Fesenko, S.N. Shulga, O.V. Bagatskaya, He Shi
scattering matrix, Rectangular waveguide, anisotropic medium
Vestnik KhNU 756 Pages. 33-37

The problem of determination of the scattering matrix coefficients from anisotropic inclusion in one side short-circuit waveguide was considered. Calculation of the scattering matrix coefficient |S10| for the anisotropic slab in the end of the empty rectangular waveguide is presented



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

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



16.  Influence of impact ionization on efficiency of rsca-diodes operation on basis of InN, GaN, AIN
D.V. Pavlenko, E.D. Prokhorov
nitrides, RSCA oscillators, oscillating efficiency, drift velocity
Vestnik KhNU 756 Pages. 109-112

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 %)



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

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



18.  Features of the forest radio emissi
L.M. Atroshenko, K.P. Gaikovich, N.N. Gorobets, V.N. Gorobets
Radio emission, a forest
Vestnik KhNU 806 Pages. 8-13

Dielectric permeability of sheet plates of deciduous breeds of trees, dependence of the level of own wood signal from its projective covering, temperature distinctions, diffraction of radiowaves and their plural reflections in a crone of trees are investigated.


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19.  THE H10 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 806 Pages. 14-17

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

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


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21.  Arbitrary falling of wave on grate with by nisotropic layer
A.I.Adonina, R.R.Naumov, A.I.Sljusarev
grate, magnetodielectric, stream of power, method of Riman-Gilbert, anisotropic, Resonator
Vestnik KhNU 806 Pages. 22-28

A decision set the problem is conducted for and pour, proper two subsystems into which the system of equalizations of Maxwell is divided for anisotropic environments. The mixed field (in the case of the arbitrary falling of wave) is determined as a sum of two types pour. Integral descriptions are from the decision of the reduced endless systems of linear algebraic equalizations, got the method of task of Riman-Gilbert. The analysis of the graphs, partly resulted in work, allows to set influencing of parameters of structure and angles of incidence of wave on an anomaly in the dissipated field for every concrete case, and also to suppose and to confirm physical reasons of existence of anomalies a numeral account, as resonances of own waves in the opened resonator which is design the explored structure.


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22.  Resonance phenomena occurring as a thin refractive cylinder diffracts the hertzian wave
Yu. I. Grebenyuk, N. G. Kokodiy, Khe Shi
diffraction, thin cylinder, Refractive index, scattering, absorption, weakening, Resonance
Vestnik KhNU 806 Pages. 33-39

On the basis of solutions to the wave equation, the efficiency of dispersing, absorbing, and weakening the electromagnetic field that a thin cylinder with a large refractive index diffracts has been estimated. The transverse and longitudinal distribution of the electromagnetic field inside and outside of the cylinder has been calculated. The resonance is found to increase the intensity of both the electromagnetic wave field inside the cylinder and the scattered wave outside. Inside the cylinder at resonance, a wave propagating along its surface arises, and under some conditions, a wave propagating through the cylinder is also generated. As the refractive index is increased, the wave tracks the cylinder surface more closely, and its intensity is progressively enhanced.


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

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


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

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


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25.  Radiolocation complex for extra-atmospheric researches
A.F. Sorokin, A.A. Sorokin, N.N. Gorobets, O.V. Sokolova
Radar, a, microwaves, space garbage
Vestnik KhNU 834 Pages. 25-30

The creation pulse radar is offered on the basis of radio engineering systems of the National centre of management and test of space means of Ukraine for the forecast asteroid of danger, cataloguing of space garbage, research of a solar crown, near a sun and interplanetary plasma, and also for radioastronomical researches of distant space. Is shown, that at use of large-sized aerials to a ADU - 1000 and P-400 such radar at length of a wave ~ 30 cm at heights ~ 105 finds out objects with the minimal sizes ~ 0,7 cm. On a disk of the Sun the spatial sanction ~ 103 kms


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26.  Earth profile plotting using pulse radar with scanning antenna array
A. S. Kutsenko, . V. Kazansky, N. N. Kolchigin
pulse radar, antenna array, Radar image
Vestnik KhNU 834 Pages. 37-41

This paper is devoted to development of radar signal processing technique which allows one to reconstruct earth profile and reveal and identify manmadc objects which arc situated on underlaying surface. The technique of signal processing and image construction is based on measuring of directional characteristics of the scene being investigated. Modeling of radar activity has been performed; radar images of some simple scatterers have been obtained. Possibility of using the technique for scene profile reconstruction and revealing of manmade objects situated on it has been shown


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27.  Far-field distance of waveguide radiators
N.N. Gorobets, E.E. Ovsyannikova, A.V. Shishkova
Rectangular waveguide, microwaves, boundary of far zone, amplitude, phase radiation characteristics
Vestnik KhNU 834 Pages. 68-76

On the basis of Hertz potentials in Kirchhoff approximation the amplitude and phase radiation characteristics of open-ended rectangular waveguide excited by TE10 dominant mode are investigated at arbitrary distance from radiating aperture. The estimation criteria of far zone boundary for small (in comparison with the wavelength) waveguide radiators are presented. For such small radiators, the classic formula for calculation of far-field distance cannot be applied. Under suggested criteria the investigation of radiation characteristics are carried out. For waveguides with the sizes less then the wavelength in the waveguide, the boundaries of far-field distance are defined


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

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


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29.  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 834 Pages. 95-99

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 hole-like centers with the hole localized on the p-orbit 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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30.  Influence of aperture-illumination law on near-field characteristics of aperture antennas
E.E. Ovsyannikova, A.V. Shishkova, N.N. Gorobets
electromagnetic waves, Reactive fields, aperture radiators, Kirchhoff technique, near-field, far-field, amplitude distributions, phase characteristics, amplitude characteristics, Reactive radiation power
Vestnik KhNU 853 Pages. 28-36

On the basis of Hertz potentials the investigation of near-field reactive region of square aperture antennas with various aperture illumination laws has been carried out. The influence of the field amplitude distribution law in the aperture on the extension of this region has been studied. The calculation and analysis of amplitude, phase and power radiation characteristics, including reactive radiation power density, at the different planes in near-field region have been carried out. The analysis of the criteria for estimation of near-field reactive region boundary has been carried out


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

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


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32.  Diffraction of the plane acoustic wave on the hard spherical segment, shielding of the ball
Rezunenko V.A.
acoustics, spherical segment, shielding ball, Resonance frequencies, algebraic equations of the second kind
Vestnik KhNU 853 Pages. 57-63

A solution of the axisymmetrical problem of acoustics in strict formulation is built. The acoustic potential of the velocity of the plane wave, diffracted on the hard spherical circular segment, shielding of the ball is analyzed. The method of regularization of the paired summarized equations is used. The method of the integral transformations is applied. The principal part of the summarized equations is isolated and inverted. The effectively solvable system of the linear algebraic equations of the second kind with the compact operator in the Hilbert space l2 is obtained. Comparison with the known results and limited cases of the problem is given. The effectiveness of the constructed algorithm is confirmed. Some resonance frequencies and generalization of the task are examined


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

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


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34.  About convergence of the mode expansions onto spherical harmonic in time domain
Kochetov B.A., Butrym A.Yu.
mode basis method, transient field, spherical modes, Ring current
Vestnik KhNU 883 Pages. 41-44

The convergence of spherical mode expansions in the time domain to the exact solution is shown on an example of a test problem that has a closed-form solution. Radiation of a ring with transient current in free space is considered. It was shown that there


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

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


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

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


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37.  On non-unique definitions the lorentz transformation
Volchenko A.P.
Rate of neutrinos, the speed of light, the phenomenon of the aberration of light, the Lorentz transformations
Vestnik KhNU 966 Pages. 82-89

IThe article shows that the Lorentz transformations (LT) if they define as an object of mathematics, allow for different geometric and as a consequence, various kinematic interpretation. In this regard, introduced by the geometric and kinematic interpretation of the corresponding SPs that do not use the postulate of special relativity, whereby the speed of light is the limit for the velocities of the bodies that have mass. The specificity of this definition is illustrated by their use of in the description of the phenomenon of aberration of light.


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

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


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39.  

Radioholographic image, Radiohologram, three-dimensional image of object, spatial resolution
Vestnik KhNU 966 Pages. 68-71

The known method of the in-phase adding up of harmonic vibrations with different temporal and spatial frequencies is examined. In ordinary aerial of accordion with different spatial frequencies in sending to the object folded in a phase and the diagram of orientation is formed thus (main and lateral petals). In other directions spatial accordions folded with different phases and fomiruyut lateral petals of diagram of orientation. If to create the multifrequency and multiposition coherent system such, that on separate aerial positions signals are accepted with different bearings frequencies, on the output of general aerial they can be laid down in a phase in certain moment of time like that as it takes a place with spatial frequencies in ordinary aerial. In this case spatial resolution of order of wave-length is provided thus.


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40.  

Radioholography, multiposition spatially-coherent system, dynamic conflict situation
Vestnik KhNU 966 Pages. 72-76

Possibility of creation of the radioholographic informative system is shown for the decision of problem tasks of modern and perspective radio-location and construction on its example of system theory of radio-location. The decision of problem tasks of radio-location brings a necessity over to determination of ways of its development, and a necessity of decision of basic problem task of radio-location systems engineering is developments system the theory of radio-location - 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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41.  

mode basis method, transient field, spherical modes, Ring current.
Vestnik KhNU 883 Pages. 41-44

The convergence of spherical mode expansions in the time domain to the exact solution is shown on an example of a test problem that has a closed-form solution. Radiation of a ring with transient current in free space is considered. It was shown that there exist only a finite number of propagating modes for any frequency at any given radius of a circumventing spherical surface. Thus within the framework of mode basis method in spherical coordinate system a finite number of main modes is sufficient to describe radiation of a transient sources located within a sphere of some given radius.


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

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


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43.  

method of enveloping surfaces in medium, synchrotron-Cherenkov radiation, Radiation spectrum, hopping variations.
Vestnik KhNU 983 Pages. 38-47

The method of enveloping surfaces is generalized for the case of the system of electrons moving along an arbitrary defined trajectory in transparent isotropic medium. The basic relationships for the classical radiation theory of the system of electrons moving in transparent isotropic medium along an arbitrary defined trajectory are obtained using this method. The hopping variations in spectral distributions of the radiation power of one, two, three, and four electrons moving along a spiral in transparent isotropic medium are studies.


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44.  

holography, physiological optics, Retina, uniaxial crystal, form-birefringence, Fresnel's formulas.
Vestnik KhNU 983 Pages. 91-101

Theoretical analysis of the laser radiation transmission at interface between the quasi-crystalline layers of the retina (a layer of nerve fibers and photoreceptor disks) is analyzed in a frame of holographic model of physiological optics. To solve the problem, we have obtained analogues of Fresnel's formulas for the interface between two uniaxial crystals. The results may be applied for diagnosis and treatment of ophthalmologic diseases by laser techniques.


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45.  

microstrip resonant antenna, thermostabilization, temperature compensation, dielectric permeability, substrate, Resonant frequency
Vestnik KhNU 927 Pages. 65-70

The results theoretical and experimental researches of opportunities thermostabilization of resonant frequency microstrip antennas are given by use two-layer dielectric of substrates with opposite on a symbol and temperature factors, close on size, dielectric of permeability. The optimum ratio between the thickness of layers in a composite two-layer substrate are given. It is shown that the experimental oscillator with temperature compensation for temperature changes from -50 to +80 C the deviation of resonance frequency in the optimal variant is less than 0,1%


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46.  

circular waveguide, coaxial waveguide, Residues-calculus technique.
Vestnik KhNU 927 Pages. 71-77

Diffraction problem of H1m waves by the system of circular slots in a hollow inner conductor of a coaxial waveguide using the operator approach is considered. The space inside a slot and between the slots is filled by a dielectric material. The diffraction problem by the gap of a semiinfinite circular waveguide placed coaxially inside a circular waveguide of lager radius is solved as the key problem. Dependencies of the transmission and reflection coefficients of bounded and semiinfinite periodical structure versus wave number and period of slots displacement are analyzed.


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47.  

Radioholographic image, flat and unflat radiohologram, by volume image of object, effect of Dopler.
Vestnik KhNU 927 Pages. 48-53

The physical and structural features of construction of the radioholographic informative systems (RG IS) and their adaptive properties which show up at forming and treatment of the coherent wave field on a transmission and reception are examined. The method of registration of radiohologram is offered on the surfaces of arbitrary form and method of adaptation of frequency of supporting oscillation to different frequencies of signal at a cooperative reception and to frequency of Dopler.


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48.  

laser, optical radiation, intensity, distribution, Receiver, direct problem, inverse problem.
Vestnik KhNU 927 Pages. 31-35

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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founded: 48 result (s)
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