S.A. Masalov and V.V. Shcherbak
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
The V.P. Shestopalov School Methodology in Theory of Wave Diffraction
The efficient mathematically rigorous solution techniques added to diffraction theory by prof.
V.P.Shestopalov and his followers in the Kharkov diffraction school are surveyed and analyzed in
anticipation for further advances that might be where the well-known methods overlap. The formulations
for and the links between different classes of the so solved problems are revised to get them more generalized.
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A.A. Zvyagintsev, A.I. Ivanov, and T.N. Demchenko
V. Karazin National University of Kharkov,
4, Svoboda Sq., Kharkov, 61077, Ukraine
Application of the Uniform Asymptotic Theory to Electromagnetic
Wave Scattering by a Half-Plane with Impedance Properties
The problem of wave diffraction by a half-plane with impedance properties is analyzed.
The theoretical results presented relate to the scattering of plane and cylindrical waves and
have been obtained within the geometrical theory of diffraction and the uniform asymptotic theory.
These results are compared between themselves, as well as with the results of other asymptotic methods.
The effect of impedance upon the scattered field is discussed. Dependences of the scattered field on the distance
from the half-plane edge are presented for a variety of impedance magnitudes.
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P.L. Tokarsky
Kharkov National University of Radio Engineering and Electronics,
14, Lenin Ave, Kharkov, 61166, Ukraine
Wave Matrices in the Analysis of Noises
of Dissipative Antenna Arrays
A matrix technique is proposed for the noise analysis of an arbitrary phased antenna array
allowing to estimate the contribution from all the internal noise sources (that may be correlated and not correlated)
with rigorous consideration for the mutual coupling between lossy radiators. The relations are obtained for calculating
the internal noise temperature on the output of the receiving phased array.
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Yu.N. Gorobets
V. Karazin National University of Kharkov,
4, Svoboda Sq., Kharkov, 61077, Ukraine
Scattering coefficient of circular-aperture antenna
The relationship between the scattering coefficient of an aperture
antenna and the type of amplitude distribution and dimensions has been studied. It is shown that there
exist optimal conditions for antenna excitation under which the maximum directivity-to-scattering coefficient ratio is provided.
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N.N. Gorobets and R.I. Tsekhmistro
V. Karazin National University of Kharkov,
4, Svoboda Sq., Kharkov,
61077, Ukraine
Characteristics of the Near-Field Zone of Short Wire Antennas
The amplitude and phase characteristics of electromagnetic (EM)
field of symmetric short thin-wire finite-length antennas in their near-field zone have been examined.
The applicability limits of the Hertzian electric dipole theory for the antennas whose length is considerably
shorter than the wavelength are determined, and the far-field zone boundaries of small electric-size wire
The amplitude and phase characteristics of electromagnetic (EM) field of symmetric short thin-wire finite-length
antennas in their near-field zone have been examined. The applicability limits of the Hertzian electric dipole theory
for the antennas whose length is considerably shorter than the wavelength are determined, and the far-field zone
boundaries of small electric-size wire antennas have been likewise specified.
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V.A. Doroshenko
Kharkov National University of Radio Engineering and Electronics,
14, Lenin Ave, Kharkov, 61166, Ukraine
Singular integral equations in the problem of wave diffraction
by a grating of imperfect flat irregular strips
A technique based on the application of the Kontorovich-Lebedev integral
transform and singular integral equations are developed for the solution of the problems
of wave diffraction by three-dimensional irregular strip gratings. The numerical solution of the
singular integral equations was obtained by discretization and application of the Gaussian quadratures.
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A.A. Barannik and Yu.V. Prokopenko
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Axial Index of "Whispering Gallery" Oscillations in Disk Dielectric Resonator
Quasi-optical dielectric disk resonators differing by their longitudinal sizes, have been investigated. Axial components of the wave number
k z of "whispering gallery" oscillations have been obtained by means of a solution of the inverse spectral problem.
Axial indexes of resonance oscillations in the resonators studied have been determined.
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V.V. Khardikov
V. Karazin National University of Kharkov,
4, Svoboda Sq., Kharkov, 61077, Ukraine
Natural Modes of a Quasi-Periodic Cylindrical Waveguide
with Reactive Irises
Natural modes of a quasi-periodic cylindrical waveguide with reactive irises are studied.
The relation between total transparency frequency bands and complex-valued eigenfrequencies
of the structure is established. The effect of natural modes
upon amplitude-frequency responses is analyzed.
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E.E. Getmanova and D.B. Kostarev
Kharkov National University of Radio Engineering and Electronics,
14, Lenin Ave, Kharkov, 61166, Ukraine
Resonance Phenomena Resulting from Excitation of Normal Modes
in Sets of Coupled Linear Oscillators
The paper studies the conditions for normal mode excitation in sets of coupled
linear oscillators with a finite number of elements. Chains with a finite number
of elements have been studied. It is shown that the character of normal mode excitation
can be varied by changing the sequence order of the oscillators, and the mode frequencies
will be changed significantly. The mathematical package Mathcad 7.0 was used for the numerical
analysis of resonance phenomena in the objects under investigation.
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N.N. Beletskii and S.A. Borisenko
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 Semimagnetic Semiconductors Being
in a Phase of Antiferromagnetic Ordering
In the articles nonlinear surface polaritons are investigated in
semimagnetic semiconductors which are in a phase of
antiferromagnetic ordering. It is shown that there exist two types
of the nonlinear surface polaritons which characterized by nonotonic
and non-nonotonic decaying of the electromagnetic field in
semimagnetic semiconductor. It is found that nonlinear surface polaritons
with the monotonic decaying electromagnetic field exist in the same frequency
range as linear surface polaritons. It is found out that nonlinear surface polaritons
with non-monotonic decaying electromagnetic field propagate in the frequency
range which is the non-passage range for linear surface polaritons.
The influence of the electron plasma frequency is determined on the
dispersion properties of the nonlinear surface polaritons.
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A.F. Rusanov and V.M. Yakovenko
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Interaction of Beams of Charged Particles with Semiconductor
Cylindrical Magnetoactive Plasma
Oscillations are investigated in a cylindrical system which is
represented as electron beam-semiconductor-dielectric (metal)
in an external magnetic field. It is shown that besides the instability
of Van Kampen waves (space charge waves of a beam) the instability
of cyclotron waves occurs in such systems. The increase of the external
magnetostatic field and the effective frequency of electron collisions in the
semiconductor tend to decrease the instability increments of these waves.
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S.A. Derevyanko, O.I. Lyubimov, and V.A. Yampolski
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Anomalous Transparency of a Thin Metal Plate Carrying a Strong Transport Current
A new anomalous penetration effect is predicted of an electromagnetic
wave into a thin metal plate with a strong d.c. current. As is shown,
the electromagnetic wave field can be driven to the opposite side of the
specimen even if spatial dispersion is strong, such that the penetration
depth is much less than the specimen thickness. The effect is due to the
group of electrons entrapped by the spatially alternating proper magnetic
field of the transport current. We also predict a cyclotron resonance for the
trapped electrons, resulting from the in periodical returns to the skin layer.
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A.V. Strizhachenko, A.A. Zvyagintsev, and V.V. Chizhov
V. Karazin National University of Kharkov,
4, Svoboda Sq., Kharkov, 61077, Ukraine
Measurement of Electrical Parameters of Uniaxial and Biaxial Crystals
A technique has been devised to measure the components of a permittivity
tensor, the axes of a permittivity ellipsoid and the optical axes of uniaxial tetragonal,
hexagonal trigonal crystals as well as biaxial rhombic crystals.
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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
On the Interaction between an Electron Beam and a Slow Electromagnetic
Wave in an O -Type Oscillator
The equation of an electron motion in a slow wave field with the
constant amplitude and its approximate solution technique are
considered on the basis of the solution expansion into power
series by the small wave amplitude. It is shown that the most
effective energy transfer mode from the beam to the wave always
lies beyond the bounds of this approximation applicability. Thereby,
this approximation is inapplicable for description of the oscillation modes
having the efficiency factor close to the maximum possible.
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Yu.V. Arkusha, E.D. Prochorov, and I.P. Storozhenko
V. Karazin National University of Kharkov,
4, Svoboda Sq., Kharkov, 61077, Ukraine
In0.4Ga0.6As Gunn Diodes with a m-n:
InP1-xAsx Cathode
The operation of the In04Ga0.6As Gunn-effect diodes with a m-n: InP1-xAsx
cathode has been investigated in terms of a two-temperature model at a crystal
lattice temperature of 300K and an active region length of 0.5; 0.8; 1.0 m. The optimal InP1-xAsx
composition is determined for each diode length. For the diode having a 10 mm-active
region an optimal height of the potential barrier on the metal-semiconductor contact
is likewise specified. It is shown that the maximum generation frequency is ~250GHz.
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D.A.Yarekha, A.N.Baranow, I.Rouyard, K.Alibert, and M.M.Bykov
Kharkov National University of Radio Engineering and Electronics,
14, Lenin Ave, Kharkov, 61166, Ukraine
High-Performance Continuous-Wave GaInSbAs/GaSb Type-II Lasers
The findings of the studies into narrow-stripe GaInSbAs/GaSb type-II
QW lasers are presented. The measurements of laser performances
have been made in a continuous-wave mode at room temperature.
The optical output power reached 20mW/facet. The interval quantum efficiency
of the lasers was found to be 89% and the power efficiency amounted to 20%.
The laser emitted in the fundamental spatial mode and operated on a single frequency
over a wide range of currents and temperatures. The side longitudinal mode suppression
was as great as 30dB. The emission wavelength could be continuously current-tuned within
0.7 to 1.2nm. The single longitudinal mode behavior was attributable to the photorefractive effect
owing to DX centers in the Te-doped emitter layer acting as a saturable absorber.
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K.I. Muntyan1 and V.A. Svich2
1State-owned Research and Industrial Association [SRIA] "Metrology",
42, Mironositskaya St., 61002, Kharkov, Ukraine
2V. Karazin National University of Kharkov,
4, Svoboda Sq., Kharkov, 61077, Ukraine
On the Measurement of Laser Radiation Beam Spatial Parameters
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