L.P. Yatsuk
V. Karazin National University of Kharkov,
4, Svoboda Sq., Kharkov, 61077, Ukraine
Potential Functions in the Problem of Excitation
of a Waveguide Filled with a Three-Layered Dielectric by a Longitudinal Magnetic Current
The paper deals with a rectangular waveguide having a three-layer dielectric filling
and a longitudinal slot in its broader wall. A convergent solution for the magnetic
field excited by the slot was obtained by using a modified eigenwave method.
First we derive potential functions for the waveguide with a three-layer dielectric filling.
These functions are then used to expand the magnetic current, which is explicitly present
in the solution obtained after the eigenwave method. The convergent series are obtained
for the partial input conductivities of the slot. The convergence rate of these series
practically does not depend on the width and permittivity of a dielectric slab inserted into the waveguide.
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L.B. Minakova and L.A. Rud
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St.,61085 Kharkov, Ukraine
Algorithms of Analysis and Synthesis of Rejection
Cells Based on the Partially Filled H-Plane Stubs in Rectangular Waveguide
Accurate mathematical models of the wave-scattering and eigenvalue problems
are used to develop an algorithm of synthesis of rejection cells based on the
H-plane partially filled stubs in rectangular waveguides. The results obtained
in the synthesis of a stub with a dielectric having €=9.5(1+i10-4)
are further been used to design of a three-pole band-stop filter.
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Ye.M. Ganapolskii
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Broadband Echo-Box of Millimeter Wave Band
for a Long-Time Delay of a Microwave Pulse Signal
The paper presents a compact echo-box for a long-time delay of a microwave pulse signal
of the millimeter wave range. Basically, the device is a quasi-optical spherical resonator
with a non-symmetically ruby sphere placed inside. The ruby sphere eliminates the mode
degeneracy and leads to the appearance of dense spectrum of nature oscillations.
Due to the high Q-factor of the resonator, the echo-box is able to store the microwave
signal power for quite a long time. In the case of a pulse signal, whose spectrum is wider
than the spacing between two adjacent lines of the dense spectrum of the resonator,
the echo-box has a wide effective transmission band. The device has the following characteristics:
the central frequency is 36 GHz, the delay time is not less than 5 microsec with the potential
of 100 dB, the transmission band is 2 GHz, the volume is 50 cm3, the weight is 300 g.
The echo-box can be implemented in the automatic calibration and potential-control systems
used for the measuring of the wave propagation characteristics in various media.
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V.S. Litvinenko, Yu.V. Prokopenko, and Yu.F. Filipov
Usikov Institute of Radio Physics and Electronics National Academy of Sciences of Ukraine
12. Academician Proscura St.. Kharkov 61085. Ukraine
Surface Electromagnetic Oscillations in a Semiconductor Sphere
Spectral characteristics of a semiconductor sphere have been originally studied.
It is shown that along with volume high-frequency oscillations, there are surface
oscillations in the sphere. Inside the sphere the amplitude of these oscillations exponentially
decreases along the radius from the resonator surface. At the large values of the polar index
a surface oscillation converts to a surface plasmon existing on a semiconductor plane boundary.
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N.N. Gorobetz and N.P. Yeliseyeva
V. Karazin National University of Kharkov,
4, Svoboda Sq., Kharkov, 61077, Ukraine
Radiation Characteristics of an Electric Dipole of Arbitrary Orientation Placed Above a Plane Screen
The uniform geometric diffraction theory is used to determine the electromagnetic field
of a radiating system in the form of an electric dipole of arbitrary orientation placed above
a perfectly conducting, infinitesimally thin rectangular screen. The screen is arbitrarily
positioned relative to the radiator and the field is considered throughout the observation space.
An algorithm is suggested for estimating and analyzing the directional and power characteristics
of the radiating system in dependence on the screen position. The maximum radiation directions,
highest attainable values of both the directive gain and the radiation impedance of the dipole
have been determined as functions of the screen position.
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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 Non-Redundant Antenna Configurations on a Hexagonal Mesh by a Random Search
This study is devoted to searching for non-redundant antenna geometry on a hexagonal mesh enclosed
in a regular hexagon with the radius up to 15 grid spacings. The search procedure consists in adding
new elements to a randomly selected node starting from an empty configuration. The goal is to find
configurations with as many elements as possible within a given hexagon radius. The results obtained
for the configurations within the radius up to 15 are presented. The comparison of these results with
those obtained by regular methods shows that the random search in certain cases is preferable as
it allows to find the configurations having larger numbers of elements.
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Y.Y. Volkolupov, M.A. Krasnogolovets, O.G. Lebedev, M.A. Ostrizhnoy, and V.I. Chumakov
Kharkov National University of Radio Engineering and Electronics,
14, Lenin Ave, Kharkov, 61166, Ukraine
On the Determination of Time Characteristics of Radiating Antennas
Presentation of pulse characteristics of radiating linear antenna at frequency characteristics
aproximations by the upper frequencies filters is considered. Calculation results of pulse
characteristics for the antenna with different values of wide-band factor are given.
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P.A.Melyanovsky and I.V.Popov
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Helical Antenna with Transversal Radiation
Symmetric vibrator, the branches of which are made as a spiral with small diameter and small
step provided considerable shortness, is considered. Resonant properties of vibrator under study
are compared with resonant properties of linear vibrator.
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V.V. Popovskiy and Yu.Yu. Kolyadenko
Kharkov National University of Radio Engineering and Electronics,
14, Lenin Ave, Kharkov, 61166, Ukraine
Adaptive Interference Compensators: Problems and Methods of Their Solution
Concept of development both of the adaptive one-channel and multichannel interference compensators (AIC)
is considered. Analysis of AIC algorithm efficiency are presented. The signal/(interference + noise)
relations at the AIC output as a function of an interference power in the support channel are given.
The levels of efficiency losses are estimated quantitatively in presence of a signal in the support channel.
Influence of the state matrix of AIC control algorithm on its efficiency is shown. Efficiency
of algorithms for different signal/interference situation is analyzed.
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I.D. Gladkoskok and V.A. Nazarenko
Kharkov National University of Radio Engineering and Electronics,
14, Lenin Ave, Kharkov, 61166, Ukraine
Field of Fresnel Zone-Focused Linear Antenna Array with
Random Errors of Excitation and Element Position
The expressions for estimating statistical field characteristics of Fresnel zone-focused linear
antenna array with random phase errors of excitation and random errors of the element positions
are derived. Graphs illustrating the dependence of these characteristics on the focus position,
and variances of the excitation and radiator position errors are presented.
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V.D. Naumenko, A.N. Suvorov, and A.R. Syrov
Institute of Radio Astronomy, National Academy of Sciences of Ukraine
12, Krasnoznamyennaya St., Kharkov 61002, Ukraine
Investigating the Temperature Regime of the Starter Cathode
in a Millimeter Wave Magnetron
The temperature regime of the starter cathode of a millimeter wave magnetron is investigated in dependence
on its operation conditions. The widespread opinion that starter cathode does not experience the back bombardment,
being located outside the interaction space of the magnetron has not been confirmed by practice.
The power dissipated at the cathode can make 1 or 2, or even more percent of the input power.
This amount is much lower than the power dissipated at the main cathode, however it should be
taken into account in the case of great duty factors to avoid shortening of the cathode longevity.
As has been found, the temperature of the starter cathode may sharply in crease already with anode
currents as low as 10 to 20% of the operating current. The magnitude of this increase depends
on the pulse waveform of the anode voltage. The longer the leading and trailing edge of the pulse,
the greater the amount of power dissipated at the starter cathode. Knowledge of the cathode temperature
required for stable operation of the magnetron, has permitted estimating the time current density
through the starter cathode. It was found to be about 1 A/cm2 for the magnetron under consideration.
Knowledge of this magnitude allowed launching investigations aimed at selecting the type of the starter cathode
for magnetrons of great durability.
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K.A. Lukin and P.P. Maksymov
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Electrostatic Fields in Reverse-Biased pn-i-pn Structures
Static electric fields are analyzed in GaAs, Si and Ge reverse-biased pn-i-pn structures.
Analytic expressions have been derived for the electric field and electric potential in uniformly
doped pn-i-pn structures. Both the geometry and the doping profile have been calculated
for the structures. Conditions for a drift current-controlled positive feedback between the p-n
junction have been established. It is shown that by properly selecting parameters of the reverse-biased
pn-i-pn structures it is possible to provide both the desired electric field distribution over
the neutral -region of the structure and the required magnitude of the multiplication factor fro
electron-hole pairs of the p-n junctions.
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D.V.Snezhko and N.N. Roshytsky
Kharkov National University of Radio Engineering and Electronics,
14, Lenin Ave, Kharkov, 61166, Ukraine
Optochemotronic Sensors: New Elements for Biomedical Diagnostic Systems.
1. Basic Concepts, Theoretical Description, Physical and Mathematical Models of the Processes
in Optochemotronic Sensors
The main principles of theory of new optochemotronic devices such as the optochemotronic sensors are presented.
Optochemotronic sensors are dedicated to the analytical investigation of bioliquid and other fluid probes
in biomedical apparatus with optical registration and data transfer through communication network
in the on-line mode operation. With allowance made for consideration presented here, the necessity
to develop a quantum-mechanical simulation of the processes in sensors of this kind has been shown
to increase selectivity and efficiency of sensors.
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V.V. Shevchenko
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Electrical and Spectral Matching in Lamp Pumping System of Pulsed Lasers
The important factors influencing operation efficiency and longevity of flashlamp-based systems
of laser pumping are analyzed. Specific features of their operation are considered for a variety
of pulse parameters. A method is suggested for designing efficient flashlamp pumping systems with
specified parameters.
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V.V. Shevchenko
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Holographic Interferometry of a Lateral Surface of KDP Crystals and Modulation
of a Laser Radiation at Resonance Frequencies
The mode pattern of resonance oscillations of electrooptical KDP crystals was investigated by using
two methods such as holographic interferometry and polarizable optics. It was found that the theoretical
solution based on the approximation of a thin plate are in a satisfactory fit to the shift oscillations
which become excited in crystals of the rectangular form (odd modes). Besides there is revealed
the existence of natural oscillations in these crystals that can be interpreted as even modes.
The conditions necessary for effective modulation of a laser beam on resonance frequencies of the
KDP crystals are determined.
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P.K. Nesterov
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Quasi-Optical Interferometers with Enhanced Phase Sensitivity
Quasi-optical interferometers are described intended for determining of electron concentration
(ne) of plasma by sounding with submillimetric waves and measuring of phase
shift of wave passed through plasma, the shift being caused by change of ne.
Design of interferometers is based on a hollow dielectric beam guide and radio-measurement
quasi-optical devices. Proposed circuits allow to increase accuracy of ne
determination in cases that values of phase shift measured by well-known interferometers
make several degrees or several tens of degrees.
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V.I. Borsch, V.V. Koval, and B.Ya. Kostik
A.S. Popov Odessa National Academy of Communications
Oscillations in Optimal-High-Speed Radioautomatics Systems
The topology of an optimal-high-speed object control has been considered.
The periodicity of the control action along the phase coordination is the main peculiarity
of such objects. The mathematical model of the control object and its transformation are represented.
The problem and specific character of its realization have been defined. The equation of the optimal
phase tracks has been suggested and using it the optimal-high-speed regimes of transient processes have
been built and analyzed.
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N.D. Koshevoy, V.À. Gordienko, Î.N. Koshevoy, and Ò.G. Rozhnova
National Aerospace University (Kharkov Aviation Institute),
17, Chkalov St., Kharkov, 61070, Ukraine
Comparative Analysis of Pressure Sensors with Digital Output
Pressure sensors of different functions are presented. Comparative analysis of pressure sensors
suggested are being conducted it allows to perform the purposeful selection of sensor for the air dashboards.
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