V.A. Doroshenko and O.A. Remayeva
Kharkov State Technical University of Radio Engineering and Electronics,
14, Lenin Ave, Kharkov, 61166, Ukraine
Integral Equations in the Problem on Longitudinal Slot Cone Excitation
The work deals with a problem on longitudinal slot cone excitation. An algorithm is given for reducing
the problem to solving the first kind singular integral equations. The algorithm is based on using Debye
potentials and Kontorovich-Lebedev integral transform. Dirichlet and Neumann boundary problems for Debye
potentials are considered. Singular equations are obtained, which have logarithmic and Cauchy singularities.
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V.L. Pazynin and Yu.K. Sirenko
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
A Two-Dimensional Model for Pulse Propagation in the Physical Environment: Proper Truncation of Computational Domain
in the Finite-Difference Method
The paper presents a two-dimensional model of radiation and propagation of pulse waves in a nondispersive medium
characterized by arbitraryly varying electric parameters and . The problem formulation is sufficiently general; throughout
the paper we will use the term 'physical environment' to mean natural and man-made media and objects surrounding humans
in their everyday activity. In other words, the approach developed permits analyzing impulse propagation both in natural and
urban environment. Special attention is paid to the problems of correct truncation of the computational domain of the finite-difference
method being among a few ones providing solutions to such complicated problems.
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I.E. Antipov and B.G. Bondar
Kharkov State Technical University of Radio Engineering and Electronics,
14, Lenin Ave, Kharkov, 61166, Ukraine
On the Super-Long Meteor-Burst Propagation of Metric Waves
The possibility of super-long meteor-burst propagation by the dual wave reflection from meteor trails and Earth surface is considered.
The Earth surface reflection is assumed to be as smooth one. The joint reception area concept is introduced. The duty cycle for super long
path sharply decreases as the distance increase and it is less than 0.1% for the 400 km path length.
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Yu.V. Kornienko
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Construction of Nonredundant Antenna Configurations on a Square Grid
by a Random Research Technique
The nonredundant configurations of an antenna array or an optical device's aperture on the squares whose side consists
of 5 to 20 elements of an integer-valued grid have been constructed using a random search technique. The results of the
constructure procedure are presented.
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Yu.V. Kornienko
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Interferometric Method of Forming Images and Optimization
of the Interferometer Apertures
Mathematical statement of the optimization problem for the input and output apertures of a
multibeam interferometer is presented, which can be applied to the interferometric method
of forming images in the millimeter and shorter wavelength bands. The results obtained by the
method of random searching are demonstrated.
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O.V. Gunko
Kharkov National University of Radio Engineering and Electronics,
14, Lenin Ave, Kharkov, 61166, Ukraine
Solving the Nonlinear Singular Integral Equation Governing
Amplitude-Phase Relations in the Communication Theory
The set of all solutions of the nonlinear singular integral equation has been construction in the space
of all the signals with compact-carrier spectra. Here is the Hilbert transformation operator. The equation describes
all the signals , and hence all the phases corresponding to the Hilbertian amplitude . The equation is reduced to a boundary-value
problem for analytical functions that is solved through factorization of the exponential type entire function .
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A.A. Mogyla
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Interrelation between Two-Parametric Models of Random
Signals with Limited Energy in Different Orthonormal Bases
An interrelation between two-parametric models of random signals with limited energy in different
orthonormal bases is established. Based on this result, interrelations between two-parametric models
of their samples and of the correlation functions of these signal components are determined. These interrelations
are obtained by using the mathematical apparatus of the Hilbert random process spaces over the Hilbert space of
samples of the Hilbert space of their weighted samples. The energy characteristics of two-parametric models of
random signals in arbitrary orthonormal bases are introduced and their interrelation is determined.
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V.P.Prokofyev and Yu.P.Chinayev
Zaporozhye National Technical University,
64, Zhukovskogo St., Zaporozhye, 69063, Ukraine
The Experimental Investigation into the Adaptive Composition System
of Space-Time Signal Processing and the Conventional Adaptive System
of Parallel Weighting Summation
The results from experimentally testing the active noise interference suppression factor, speed of response and
sensitivity to hardware errors in the multichannel adaptive systems with parallel and parallel-serial signal processing.
The data thus obtained serve to validate the theoretical inferences about the advantages of systems with parallel-serial
signal processing (composition adaptive systems).
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N.I. Kravchenko and D.V. Lenchuk
Kharkov National University of Radio Engineering and Electronics,
14, Lenin Ave, Kharkov, 61166, Ukraine
Simulation of Error Analysis in a Digital Frequency Meter
for Meteorological Signals
The structure design of a digital frequency meter for meteorological signals is analyzed
for the case of coherent signal packets . The errors due to discrete data taking are studied,
and ways of reducing their magnitude are suggested through increase in the number of frequency
channels and interpolated corrections of the maximum likelihood estimates. Mathematical modeling
is used to obtain and display the dependences of the root-mean-square error of frequency
measurements on the number of pulses in a packet, the number of frequency channels,
repetition frequency of the processed pulses and the signal-to-noise ratio.
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A.I. Vershina and A.G. Markin
Zaporozhye National Technical University,
64, Zhukovskogo St., Zaporozhye, 69063, Ukraine
Determining the Sensitivity Functions in Dynamics
In this paper, we consider the possible ways to improve the efficiency of computing the sensitivity functions in the
simulation of electronic circuits with many variable parameters. The formulas leading to a new solution of this problem
are derived.
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N.N. Beletskii and Yu.V. Bludov
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Nonlinear Surface Polaritons in a Two-Dimensional Electron System Placed Into a Quantizing Magnetic Field
Nonlinear surface polaritons (NSP) are theoretically investigated in an isolated two-dimensional electron
system (2DES) arranged at the boundary between linear and nonlinear media and placed in an external
quantizing magnetic field directed parallel to the 2DES. It is assumed that the nonlinear medium dielectric
permittivity depends on the tangential component of the electric field only. It is shown that under the integer
quantum Hall effect conditions all NSP characteristics are quantized magnitudes. It is found that the NSP
spectrum contains two NSP modes – high-frequency and low-frequency ones. It is shown that the NSP may
exist only in the case when the value of the electric field tangential component at the boundary is less than
certain critical value. It is found that the high-frequency mode of the NSP undergoes the resonant interaction
with the surface polariton existing in the vicinity of the cyclotron resonance subharmonic.
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V.S. Popov
V. Karazin National University of Kharkov, 4, Svoboda Sq., Kharkov, 61077, Ukraine
On Instabilities of Bounded Plasma with Current
Dispersion equations of surface waves in the half-space and the layer filled by cold electron-ion
plasma electrons of which move at steady speed about ions, are obtained and investigated in a
hydrodynamic approximation. It is shown that in the case of very slow surface waves solutions of
dispersion equations can be presented in an analytic form. Possibility of appearance of unstable
oscillations is noted. Spectrum boundaries and nature of instabilities are determined.
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V.D.Yeryomka, A.A.Kurayev, T.L.Popkova, and A.K.Sinitsyn
Belorus State University of Computer Science and radio Electronics,
6, P.Brovka St., Minsk, 220027, Belorus
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov, 61085, Ukraine
Efficiency Optimization of a High-Power O-Type TWT
on a Irregular Corrugated Waveguide
A self-consistent two-dimensional nonlinear theory has been formulated of a relativist
O-type TWT with slow-wave structure TWT. This structure represents an arbitrarily-irregular
smooth waveguide in which the electron interaction forces are averaged. Equations of
excitation have been derived by the coordinate transformation procedure.
A solution to the problem of optimizing the relativist O-type TWT efficiency
has been found using the atomic functions to approximate the sought-for optimal slow-wave
structure profile. A new mechanism for the efficiency-optimized interaction has been disclosed,
enabling the process of phase synchronized focusing of an electronic packet (its center is
coincident with the nodal point of field forces) to be sequentially repeated and the power
to be extracted from an electron bunch (the mode of the bunch is kept at a maximum
of the retarding field phase).
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V.A. Antonov, I.A. Viazmitionov, I.V. Lopatin, and
A.S. Tishchenko
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Current-Density Analyzer for Thin Ribbon Electron Beams
with High Specific Power
An investigation technique is suggested and an analyzer is developed
for the determination of the absolute values and of the current-density
distribution at the cross-sections of thin magnetically-limited ribbon electron beams
with a power density of more than 100 kW/cm2, the continuous static formation-modes
being corresponding to real operation conditions of medium-power diffraction-radiation sources.
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V.V. Maslov
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Solvent Effects upon Active Media Characteristics of Dye Lasers
The intermolecular interactions in working solutions of laser dyes (bensopyran derivatives) is analyzed
for the case of generation under lamp excitation. Comparative analysis was made for three classes of
water soluble dyes.
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Yu.G. Shkorbatov and V.G. Shakhbazov
V. Karazin National University of Kharkov, 4, Svoboda Sq., Kharkov, 61077, Ukraine
Effect of Microwave Irradiation on Biological Objects
The overview and the analysis of extensive literature evidence for the effects of low-intensity electromagnetic
fields (EMF) of microwave band on biological objects are given. The EMF effects are considered at different levels
of organization of biological systems: molecular, subcellular and cellular. Some data on the microwave influence on a
whole organism are presented. It is shown that the effects of low-intensity microwave irradiation are displayed at all
levels of biological system organization. In the author's point of view, of particular significance in determining the
response of eucaryotic organisms to irradiation is the reaction of cell nucleus. This reaction is specifically judged from
the changes in the bioelectric properties of nuclei and chromatin. The hypothesis of one of the authors as to the role
of intrinsic electromagnetic radiation of the nucleus in controlling the cell response to external EMF is considered.
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V.G. Shakhbazov**, N.N. Grigor'eva**, L.M. Chepel**,
S.P. Sirenko*, T.M. Cheshko**, V.I. Kiyko**, and N.N. Gorobets**
* A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
** V. Karazin National University of Kharkov, 4, Svoboda Sq., Kharkov, 61077, Ukraine
Effect of Electromagnetic Radiation and Temperature
on Wheat Seed Viability
The influence of electromagnetic radiation (EMR) of microwave (MW) or EHF ranges and
He-Ne laser rays on thermal stability of wheat seeds was investigated. The energetic dose
density was common for all the types of radiation under study, being 840 mJ/cm2 or 126 mJ/cm2
in different sets of experiments. The seeds were warmed-up in a water thermostat at 52 oC for 20 min.
The EMR effect was examined prior to and after the seed warming-up with different time intervals
(5, 60 min and 24 hours) between the impacts of the above factors. The seed reaction was judged from
the germination percentage. The results obtained suggest the EMR ability to modify the thermal stability
of wheat seeds. The protective effect was observed for the seeds being irradiated after warming-up.
In some cases the seed irradiation prior to warming-up was conducive to the sensibilization effect.
The similarities in the seed reaction to EMR with different wavelengths but the same energetic dose
density were revealed. The present study can be regarded as a model of reactions occurring not only in t
he seeds but also in other biological objects, including human organism. This should be taken into account
in using a variety of physiotherapy methods.
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V.N. Rodionova, V.A. Karpovich and G.Ya. Slepyan
Institute of Nuclear Problems, Belarus State University, 11, Bobruiskay St., 220050, Minsk, Belarus
Investigations Carried Out Over the MW-Range: Electrodynamics of Resonance Systems Put Forward for Solving Science-Related
and Applied Problems
Theoretical and experimental investigations has been made into the principles of improving the
Q-factor, mode selection, and wide-band matching of all types of resonators with single-mode
rectanqular waveguides at frequency range from 0.6 to 180 GHz.
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A.A. Mogyla, K.A. Lukin, and Yu.A. Shyian
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Relay-Type Noise Correlation Radar for the
Measurement of Range and Vector Range Rate
The problems of practical realization of noise signals optimal reception and development
of noise radar for measurement of range and range rate vector are considered. It is shown
that an output signal-to-noise ratio of relay-type correlation receivers could degrade by 2 dB
in comparison with that of the optimal receiver. The radars considered have a high clutter immunity
that enables one to make unambiguous measurements with high accuracy and resolution.
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A.V. Zabolotny, M.D. Koshevoi, and V.A. Gordienko
National Aerospace University (Kharkov Aviation Institute),
17, Chkalov St., Kharkov, 61070, Ukraine
Improving Efficiency of the Quality Control of Substances
with Dielectric Properties
Analysis had been carried out to determine the validity and hardware design of the currently existing
instruments intendent to measure the moisture content of derivatives and the trend of their further
improvement and development.
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G.V. Snezhnoi and M.V. Matyushin
Zaporozhye National Technical University,
64, Zhukovskogo St., Zaporozhye, 69063, Ukraine
Mechanism of Metal Film Sputtering under Influence of Atomic Hydrogen
Studies are reported of the processes at the surface and in the gas phase during atomizing of metal
films under influence of atomic hydrogen. Specifically, germanium crystals with Cu films (d=m)
processed by atomic hydrogen at normal temperatures are considered. The mechanism of film atomizing
in the model systems is discussed.
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