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.  Radiation of electromagnetic waves by the system of transverse and longitudinal slots in the wide wall of rectangular waveguide
S.L. Berdnik
antenna array, Multi-frequency antenna, slot system, Multimode rectangular waveguide
Vestnik KhNU 712 Pages. 25-29

The problem of radiation of electromagnetic waves by the double-frequency multielement slot array on a multimode waveguide was solved by the Galerkin's method. The radiating aperture is two systems of longitudinal and transverse slots in the wide wall of the rectangular waveguide. The power and directional characteristics of such structure were investigated. Thickness of the waveguide wall, interior and exterior interactions between slots were taken into account at calculations



3.  Stochastic fields optimal processing in MPSAR
A.V. Ksendzuk
Multiposition system, synthetic aperture, stochastic model, combined estimation
Vestnik KhNU 712 Pages. 30-32

This paper represents optimal combined estimation algorithm in multiposition synthetic aperture radar as- signed for estimation of the parameters, contained in correlation function of the complex scattering coefficient; the most important special cases were presented



4.  Application of the digital holographic interference microscope for investigation of human red blood cells 3-D morphology
T.V. Tishko, V.P. Titar, D.N. Tishko
digital holographic interference microscope, erythrocyte, Morphology, sphericity coefficient, diagnostics, Micro-object
Vestnik KhNU 712 Pages. 52-55

Results on the digital holographic interference microscope for 3-D 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 3-D morphology is very important diagnostics characteristics in medical practice. The digital holographic interference microscope is an effective device for the purposes of medical diagnostics



5.  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.



6.  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



7.  Modelling of holographic radar with discrete and continuous aperture
B. Kochetov, A. Butrym
holographic radar, Method of maximum likelihood, point scatter
Vestnik KhNU 712 Pages. 76-79

Images of a point scatter are investigated that are obtained with a model of holographic radar with discrete and continuous aperture, under illumination with planar or spherical wave. Main features of the scatter image are revealed and their dependence on parameters of the radar (aperture dimensions, elements spacing in the gratings, type of illumination) are studied



8.  The influence of the inner chanal of a periodic iris-loaded circular waveguide concerning its eigenmode mutual transformations
He Shi, S.K. Katenev, S.N. Shulga
dispersion, Brillouin diagram, Mode transformation
Vestnik KhNU 712 Pages. 80-83

The mutual eigenmode transformations are considered of a periodic iris-loaded 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.  GaAs-Gunn diodes with small levels of power constitution for mm-range oscillators
E.D. Prokhorov, A.V. Dyadchenko, N.E. Polyansky
Gunn diodes, Microwave powers, efficiency, generators mm-range
Vestnik KhNU 712 Pages. 115-118

Experimentally investigated small level operating power GaAs generators mm-range. Samples of diodes made in Problem laboratory of semiconductor engineering of the Karazin Kharkov National University. GaAs -Gunn diodes oscillators operated in continuous mode. The obtained experimentally operated powers made 10...30 mW, the useful microwave powers - 0,1...0,3 mW at an efficiency of 1...2 % over the range frequencies of 60...75 GHz. Probably further reduction consumed by diodes and oscillators of power up to hundreds and tens 10-3W



10.  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



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. 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



12.  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 Riman-Hilbert problem
Vestnik KhNU 756 Pages. 51-56

The decision of a task in view is carried out for and 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 Riman-Hilbert 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 absent-minded field for each concrete case



13.  THE INFLUENCE OF MUTUAL COUPLING ON RADIATION CHARACTERISTICS OF ANTENNA ARRAY FOR VIDEOPULSE EXCITATION
O.V. Kazansky
Mutual coupling, finite TSA arrays, Van-Atta array, videopulse
Vestnik KhNU 756 Pages. 57-60

In paper antenna array from finite number of the elements, which are exited by a videopulse is observed. The model for calculation of radiated fields of antenna taking consideration of mutual coupling between elements is proposed. A directed characteristics analysis of the retrodirected systems, Van-Atta array, from finite number of elements and wave form of radiated and reradiated signals are investigated in case of excitation by a videopulse. Recommendations to decrease mutual coupling is proposed. The case of useful influence on characteristics of a radiated pulse signal is considered



14.  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



15.  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.



16.  CALCULATION and EXPERIMENTAL MEASUREMENT OF ANODE BLOCKS PARAMETERS OF MAGNETRONS
K.M. Basrawi, G.I. Churyumov
Magnetron, anode block, Q quality factor, loaded Q factor, equivalent capacity, Mode
Vestnik KhNU 756 Pages. 132-138

In this paper the outcomes of calculation and experimental measurements of cold parameters of the pulse and continuous X - range magnetrons are presented. The measuring and calculation techniques of equivalent capacities of the anode blocks of the magnetrons as well as Q quality factor, loaded Q factor and external Q factors of the resonant system for main N/2 - mode and nearest N/2 -1 and N/2 -2 -modes is given



17.  Directed and polarization characteristics of the aperture of the circular waveguide with impedance flange
N.N. Gorobets, V.M. Dakhov, I.V. Gorbach
Microwave, antennas, waveguides, polarization, pattern
Vestnik KhNU 806 Pages. 3-7

The amplitude and polarization patterns of the radiator in the form of the aperture of circular waveguide with impedance flange, excited by the dominant wave, have been measured by the method of the indicator antenna with polarization plane rotation. It is shown that such radiators have an axial-symmetric pattern, a wide polarization pattern and a low level of side lobes.


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18.  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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19.  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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20.  Way of transformation of the patterns of reception antennas
A.A. Sorokin, A.F Sorokin, O.V. Sokolova, R.N. Zaluzhniy, N.N. Gorobets
Mirowaves, antennas, pattern, Frenel zones
Vestnik KhNU 806 Pages. 29-32

the expedient of management by the shape of directional diagrams with the help of a fragmentation of Frenel zones is offered. Measuring the shape of a pattern diagram of the horn and spiral antennas are carried out. Peak allocations a builder of a field in short-range, medial and long-range bands for different frequency range are received and analyzed. By results of experiments intensity, a corner, radius for long-range and short-range bands is constructed 3D images.


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21.  Mode basis method for open dielectric waveguide
A. Butrym, M Legenkiy
Mode basis method; open waveguide, eigenmode
Vestnik KhNU 806 Pages. 44-47

The Mode Basis Method construction for the rectangular waveguide with the dielectric insertion when one of the walls of the waveguide is removed to the infinity is considered. Spectrum division into the discrete (surface waves) and continuous parts is analyzed. The range of the continuous change of the spectrum parameter, the presence of the accumulation point and the finite numbers of the discrete modes is revealed. The formulae of the field expansion over the eigenmode of the structure are obtained.


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22.  CALCULATION AND MEASURING OF IMPEDANCE OF IMPATT-DIODE IN MILLIMETR WAVE
A.V. Arkhipov, V.T. Plaksiy, I.K. Kuzmichev, E.D. Prokhorov, A.V. Dydchenko, D.P. Chuechkov
Millimeter wave range, impedance, IMPATT diode, conductance, susceptance
Vestnik KhNU 806 Pages. 59-64

The calculated and experimental results of the impedance of the impact avalanche transit-time (IMPATT) diode for the 8 millimeter wavelength range have been presented. The dependences of the IMPATT diode impedance as a function of the normalized amplitude the fundamental current harmonic of the p-n junction and frequency have been calculated and measured. The apparatus and measuring method of the conductance and susceptance of the IMPATT diode has been developed


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23.  QUEST AND CREATION OF NOVEL ACTIVE MEDIA FOR DYE LASERS IN IRE NAS OF UKRAINE
V.V. Maslov
laser dye, Molecular structure, spectrum, fluorescence, quantum yield, lasing efficiency, photostability
Vestnik KhNU 806 Pages. 92-98

Numerous studies of novel active media for dye lasers fulfilled in IRE NAS of Ukraine are generalized in present review. Peculiarities of spectral, fluorescence and lasing characteristics of some laser dye classes for visible region of the spectrum have been analysed. A special attention is focused upon effects of structure of the dye molecule and its solvent environment on these characteristics. The outlook of development for dye-doped active media has been discussed


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24.  Dispersive characteristics of magnetoplasma waves in the rectangular wave guide with InSb
O.A. Zamuraev, O.O. Puzanov, A.S. Tishchenko
Magneto-plasma wave, semiconductor plasma, dispersive characteristics, nitric temperature
Vestnik KhNU 834 Pages. 3-7

Frequency dependence of characteristics of magnetoplasma waves in the rectangular wave guide, containing longitudinal and cross-section - 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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25.  The exitation Hp0 -waveguide wave of the Tbrunching 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 834 Pages. 8-12

In strong electrodynamics statement the problem of excitation Hp0 waveguide a wave by of the T-branching with two types matching resonator is solved: other-world and through passage. Results of calculation of amplitude-frequency 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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26.  Radiolocation complex for extra-atmospheric researches
A.F. Sorokin, A.A. Sorokin, N.N. Gorobets, O.V. Sokolova
radar, a, Microwaves, space garbage
Vestnik KhNU 834 Pages. 25-30

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


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27.  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 834 Pages. 63-67

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 cross-section 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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28.  Far-field distance of waveguide radiators
N.N. Gorobets, E.E. Ovsyannikova, A.V. Shishkova
rectangular waveguide, Microwaves, boundary of far zone, amplitude, phase radiation characteristics
Vestnik KhNU 834 Pages. 68-76

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


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29.  Electromagnetic waves focusing inside dielectric cylinder
N. N. Gorobets, N. N. Stasjuk
Microwaves, dielectric cylinder, plane wave, focusing points
Vestnik KhNU 834 Pages. 77-84

Computation and analysis of electrical and magnetic field amplitudes at focusing points inside dissipative dielectric cylinder illuminated by plane linear polarized wave have been performed using the approximation of geometric optics. It was shown that in the focal region fields vary according to oscillating law and field longitudinal gradients the more cylinder diameter and dielectric permittivity, the large at that. Results of investigation allow to explain subthreshold (nonthermal) exposure of millimeter and submillimeter electromagnetic waves on human and other biological objects


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30.  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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31.  Arbitrary falling of wave on grate with by a screen and layer of environment
A.I.Adonina, R.R. Naumov, A.I.Sljusarev
grate, Magnetodielectric, stream of power, Method of Riman-Gilbert, resonator
Vestnik KhNU 853 Pages. 45-50

A decision of the set problem is conducted in the exact raising without imposition of limits on the parameters of structure, angles of incidence of wave, wave-length, parameters of environment. The variant of method of Riman-Gilbert was used for the case of the arbitrary falling of wave. A vectorial task is presented as a sum of two scalar tasks, proper subsystems into which the system of equalizations of Maxwell is divided for - and -fields. A numeral account, resulted in work as the graphs, confirms assumption about physical reasons of existence of anomalies, as resonances between active spectral accordions and own waves of the opened resonator which designs the explored structure


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32.  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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33.  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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34.  Construction of mode basis for open dielectric structures by integral equation method
Legenkiy M.N., Butrym A.Yu.
Mode basis method, open waveguide, eigenmode
Vestnik KhNU 883 Pages. 50-53

A new method based on integral equation formulation is proposed for construction of mode basis in open dielectric waveguides. Decomposition of the spectrum in such structures into discrete (surface wave) and continuous (volume wave) part is analyzed. Disp


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35.  Investigation of different temperature modes of auxilliary cathode work in magnetrons with cold secondary-emission cathode
Avtomonov N.I., Vavriv D.M., Sosnytsky S.V.
Magnetron, cathode, thermionic cathode, thermo emission, temperature
Vestnik KhNU 883 Pages. 73-82

A theoretical investigation of the emission current temperature dependence of the auxiliary cathode in magnetrons with cold secondary-emission cathodes is performed. Different methods of providing a spatial-charge limited emission from the auxiliary catho


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36.  Determination of optimal parameters of a magnetocardiographic hexagonal measuring grid
A.Yu. Kostiev, A.Yu. Butrym, S.N. Shulga
Magnetocardiography, gradiometer, current dipole, sensitivity, Hessian
Vestnik KhNU 883 Pages. 25-29

The article considers hexagonal grid of gradiometer sensors of magnetic field. The aim of the study is to determine the optimal parameters of the grid and the gradiometers in order to obtain maximum sensitivity of the measuring system in terms of location


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37.  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 883 Pages. 59-66

The longitudinal slot is cut in wide wall of rectangular waveguide with three-layer 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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38.  ABOUT SPURIOUS RESONANCES IN PROBLEMS OF DIFRACTION WAVES ON WAVEGUIDE DISCONTINUITY
Mizernik V.N., Shmat'ko A.A.
spurious resonances, a branching of the waveguides, Mathching uniformity, connection area, system of the linear algebraicequations
Vestnik KhNU 883 Pages. 67-72

In work it is shown, that the problem of existence of spurious resonances in problems of diffraction waveguide waves on various discontinue in waveguides is connected with incorrect representation of matrix elements of system of the linear algebraic equat


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39.  Microstrip structures with photonic band gap
Fesenko V.I., Sukhoivanov I.A., Shul'ga S.N.
photonics band gap, Microstrip, filter
Vestnik KhNU 883 Pages. 20-24

In this paper, it is presented a two-sided one-dimensional photonic bandgap microstrip structure. The structure is obtained by etching a one periodic pattern of circles in the ground plane of a microstrip line and variation of the characteristic impedance


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40.  Own magnon polariton surface modes in the open passage resonator with gyromagnetic medium
Mizernik V.N., Shmat'ko A.A.
Magnon polatiton oscillations, the ferrite resonator, a junction of waveguides, the through passage open resonator, wavegaide inhomogeneity, area of connection, system of the linear algebraic equations.
Vestnik KhNU 966 Pages. 31-36

The problem about owen modes of the open reentrant resonator partially filled is theoretically solved by gyrotropic ferrite medium and existence magnon polatiton surface (PS) mods with tall concentration of a field on boundary line of the ferrite resonator is established. The every possible combined regimes of existence of superficial and volumetric fashions are analysed, dependences of their resonant frequencies on material parameters of medium and geometrical sizes of the resonator and a ferrite layer are certain.


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41.  New statistical methods of recognition and classification for automatic interpretation of remote observations
Koltunov Y.A., Dumin O.M., Katrich V.A., Naumov R.R.
Methods of recognition and classification, blenderized models of the probabilistic distributing, teaching selection
Vestnik KhNU 966 Pages. 37-49

Mathematical models, computational algorithms, and also prospects of development and application of three new methods of recognition and classification (RC), namely, construction of distinctive characteristics of objects; classification on the basis of probabilistic teaching selection with optimization of method RAC; account of dynamics of features of recognized objects are presented in the article. Recognition and classification is an area of modern science that have a boundless list of applications in all spheres of human activity. From the list of applications the only one is selected in the present work, but the most actual one, that is the remote sensing of ground surface in radiofrequency band with the purpose of study and maintainance of natural resources of Earth.


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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 966 Pages. 90-96

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.  The geometrical approaches to the calculation of propagation of Gaussian beams in hollow metal waveguides in the terahertz range
Gurin O.V., Degtyarev A.V., Maslov V.A., Svich V.A., Senyuta V.S., Topkov A.N.
Metal waveguide, Gaussian beam, terahertz range, geometrooptical approach, transmission coefficient
Vestnik KhNU 966 Pages. 3-8

A comparison of the results of calculations of the transmision for Gaussian beams in hollow circular metal waveguide using geometrooptical procedures by Frost and Crenn with the results of experiments in the terahertz range is performed. The conditions of applicability of these methods to study the transmission characteristics of metallic waveguides of different lengths were found. It is shown that in this range the geometrooptical approach, proposed by Frost, provides satisfactory results only for short waveguides, the length of which corresponds to the condition of the near zone. The geometrooptical approach by Crenn is applicable to both short and for long waveguides.


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

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


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45.  

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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46.  

Magnetron, cathode, thermionic cathode, thermo emission, temperature.
Vestnik KhNU 883 Pages. 73-82

A theoretical investigation of the emission current temperature dependence of the auxiliary cathode in magnetrons with cold secondary-emission cathodes is performed. Different methods of providing a spatial-charge limited emission from the auxiliary cathode are studied in order to eliminate the temperature dependence of auxiliary cathode thermionic current. A new design of the auxiliary cathode is proposed, which is supposed to provide a greater stability with respect to the cathode temperature variations as compared to the currently manufactured magnetrons.


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47.  

photonics band gap, Microstrip, filter
Vestnik KhNU 883 Pages. 20-24

In this paper, it is presented a two-sided one-dimensional photonic bandgap microstrip structure. The structure is obtained by etching a one periodic pattern of circles in the ground plane of a microstrip line and variation of the characteristic impedance as a function of the length of the microstrip line. The calculated scattering parameters of the proposed filter are presented.


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48.  

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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49.  

slot, Microwaves, waveguide, dielectric, admittance, scattering parameters
Vestnik KhNU 883 Pages. 59-66

The problem of a longitudinal slot radiation is cut in wide wall of rectangular waveguide with three-layer 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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50.  

spurious resonance, a branching of the waveguides, Matching uniformity, connection area, system of the linear algebraic equations.
Vestnik KhNU 883 Pages. 67-72

In work it is shown, that the problem of existence of spurious resonances in problems of diffraction waveguide waves on various discontinue in waveguides is connected with incorrect representation of matrix elements of system of the linear algebraic equations (SLAE) which lead to features at their numerical decision. On an example of a problem of diffraction waveguide waves on the -branching of rectangular wave guides it is shown, that spurious resonances correspond to resonances of area of connection of waveguides. This computing mistake can be rather simply corrected due to correct representation of matrix elements SLAE which has no features. Results of calculations have shown efficiency of such approach for the decision of problems on own oscillations and problems of diffraction on the -branching of hollow wave guides, and tees with dielectric and ferrite resonators in the field of connection of waveguides.


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51.  

waveguide resonator, Misalignment of the mirrors, terahertz range, energy losses, Mode composition, polarization
Vestnik KhNU 983 Pages. 18-22

The influence of the curvature of the spherical mirror for metallic waveguide resonator of submillimeter laser (lambda = 0.4326 mm) on energy losses and the mode composition of radiation is investigated. It is shown that the presence of quadratic phase aberrations in the mirrors of the waveguide cavity with an increase of its Fresnel number at monotonically decreasing of the energy losses for fundamental asymmetric mode TE11q due to a decrease of waveguide losses also leads to their substantial non-periodic oscillation.


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52.  Impact of random variations of air hole diameters and random variations of the centers position of air holes on operation parameters of a solid core microstructured optical fiber
A.I. Filipenko, A.N. Donskov
finite-element method, Gaussian distribution, inclusions diameter, total mode field power, angular positioning, Microstructured optical fiber.
Vestnik KhNU 983 Pages. 29-32

We investigated the impact of random variations of air hole diameter and random variations of the centers position of air holes on operation parameters in the case of solid core microstructured optical fiber with a ring of air holes. The found results show that at any of considered defect types mode field will have two pronounced maximums. At practical use an investigated type of the MOF special angular positioning end faces of fibers is necessary. We also have shown that random variations of inclusions diameter can increase total mode field power. In our research we used finite-element method.


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53.  

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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54.  

resonant photodiode, quantum efficiency, Modulation characteristic, transfer matrix method.
Vestnik KhNU 983 Pages. 54-66

In this paper, we have described methods of modeling of resonant cavity photodiods based on semiconductor quantum dimensional structures for ultrashort connections. The problem of misalignment of operating wavelength of emmiter and receiver has been shown and quantum efficiency maxima spectral shift temperature dependence was analysed. Technological control of layer thickness using laser interferometer with 1 atomic layer quality control was shown. Comparative analysis made in this paper of modulation characteristic of regular and resonant cavity detectors shows more than 5 times increasing quantum efficiency and modulation band product in resonant detector case.


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55.  

optical element of the cylindrical form, light scattering, Monte-Carlo method, indicatrix of scattering, index of refraction
Vestnik KhNU 983 Pages. 67-71

Modeling of characteristics of optical spectral-selective elements of the cylindrical form with the increased value of the refraction index, using effect of light scattering is organized. The parameters of the optical element materials, forming its spectral-selective characteristic are determined. As have shown results of researches, application of cylindrical optical element for spectral angular selection is possible in limited range of values of the index of refraction. At increase in value of refraction index before determined level the optical element starts to function in a mode of quasi uniform light scattering.


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56.  

abnormally low reflection, Metamaterials, antireflection channels.
Vestnik KhNU 983 Pages. 102-106

The physical features analysis to describe formation the regions with extremely low reflection of electromagnetic radiation in the terahertz and far infrared ranges are presented and these regions should be observed in many experimental studies. It is shown that in case of sufficiently small damping of polar phonon the spectral bands with almost complete reflection disappearance (R <0.01%) are formed and we name these bands as antireflection channels (ARC). ARC located outside the region of negative dielectric permittivity, and the minimum reflection is shifted above the frequency of longitudinal oscillations by the value depends on the basic parameters of the polar vibrations.


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57.  

GaAs diodes, drift speed, lag, coefficient frequency conversion, Maximum frequencies.
Vestnik KhNU 927 Pages. 11-14

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/(Vs) (GaAs) more than the KFC in 1000 sm2/(Vs) mobility (without NDC) in 5 times. At the further increase voltages in the mobility ratio of KFC 8000 sm2/(Vs) to KFC for 1000 sm2/(Vs) 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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58.  

geomagnetic field variations, Magnetoconjugate solar terminator
Vestnik KhNU 927 Pages. 85-89

This paper analyzes quasi-periodic geomagnetic field variations in 1 1000 s period range that connected with the magnetoconjugate solar terminator action in 2002 2008. The measurements have been made near Kharkiv city. The processing was made separately for two seasons: summer and winter solstices. Magnetoconjugate solar terminator causes the perturbations relatively the solar terminator moving at the height of 100 km with the lead time 80 100 min. Dominant periods were 10 12 min and the duration was 50 60 min. Their amplitudes attain a value of 1 2 nT. These variations are transferred from magnetospheric region by magnetoacoustic waves.


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59.  

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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