Telecommunications and Radio Engineering, 65(20)

G.V. Maistrenko and A.M. Rybalko
Kharkov National University of Radio Engineering and Electronics,
14, Lenin Ave, Kharkiv, 61166, Ukraine
Study on Efficiency of Interference Suppression by the Two-Element Antenna Array
Influence of system disagreement on a corner of directional pattern zero formation and unbalance of weight coefficients on operating efficiency of the two element adaptive antenna is studied in detail. The small view-finding mistakes of a noise source result in intense impossibility to attain the directional pattern zero is shown. The noise pollution capacity of a output signal arising from discrepancy of the weigh factors vector assignment is proportional to the total dispersion of amplitude and phase mistakes.

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S.V. Kukobko, S.V. Nechitaylo, A.Z. Sazonov, and O.I. Sukharevskiy Military Scientific Centre,
6, Svoboda Sq., Kharkiv, 61043, Ukraine
Radiation Field Calculation of an Antenna Array with a Dielectric Nose Radome
For a two-dimensional antenna array under an ogive radome, a technique for radiation field calculation is suggested based on solving the integral equation for the field in a radome wall layer. The calculation results of the array radiation pattern are presented for different scanning angles. The radome contribution to the array radiation field is considered.

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I.V. Ivanchenko, A.M. Korolev, V.L. Pazynin, N.A. Popenko, and M.M. Khruslov A. Usikov Institute of Radio Physics and Electronics,
National Academy of Sciences of Ukraine
12, Academician Proskura Str., Kharkiv 61085, Ukraine
The Features of Radiation Pattern Formation of the Monopole Antenna with Finite Screens
The ways of formation of the different directional patterns for the coaxial monopole antennas have been proposed and analyzed on the basis of experimental and theoretical investigations. As a result of the theoretical analysis of the electromagnetic field near antenna the field contribution scattered of its separate elements for the antenna pattern formation has been shown. The monopole antennas designs as a basic one for the design of the compact and effective direction finger as well as arrays antenna have been proposed.

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A.V. Arkhipov¹, I.K. Kuzmichev¹, O.G. Nechaev¹, and D.G. Seleznyov²
¹A. Usikov Institute of Radio Physics and Electronics,
National Academy of Sciences of Ukraine
12, Academician Proskura Str., Kharkiv 61085, Ukraine
²Institute of Radio Astronomy, National Academy of Sciences of Ukraine
4, Krasnoznamennaya Str., Kharkiv 61002, Ukraine
Open Resonator with an Active Microstrip Array
The present paper examines a hemispherical open resonator (OR) whose flat mirror is completed with an amplifying module. This module acting as a power amplifier is structurally incorporated with a four-element microstrip array (MSA). The experimental curves pertaining to the resonance transfer factor of the OR excited by the amplifying module and the MSA are presented. All the measurements have been made at the X-band. This open electrodynamics system is shown to be promising in terms of measuring the permittivity of substances with high losses.

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Yu.V. Svishchov
A. Usikov Institute of Radio Physics and Electronics,
National Academy of Sciences of Ukraine
12, Academician Proskura Str., Kharkiv 61085, Ukraine
Axially-Nonsymmetrical Eigen Oscillations in an Open Resonator with Spherical Mirrors
The rigorous mathematical model described axially-nonsymmetrical eigen oscillations of open resonators with spherical mirrors has been developed. Under the assumption that the spectrum of complex eigen frequencies of the open resonator exists, it has been proved that the spectrum is discrete, finite-multiple, and with the only thickening point at infinity. The spectral characteristics of the open resonator have been studied theoretically for the case when the wavelength is comparable with the resonator dimensions. The scope of correctness of some well-known asymptotic models of the open resonator has been found.

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I.V. Ruzhentsev and A.V. Marchenko
Kharkiv National University of Radio Engineering and Electronics,
14, Lenin Ave, Kharkiv, 61166, Ukraine
Spectral Analysis of the Correlation Function for the Thickness Measurements by EMA Method

A new way of processing the ultrasonic fluctuations reflected from a bottom of a product, making it possible to raise considerably sensitivity EMA method and to simplify procedure of metal products thickness measurement, is described.

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V.A. Soshenko and O.V. Sytnik
A. Usikov Institute of Radio Physics and Electronics,
National Academy of Sciences of Ukraine
12, Academician Proskura Str., Kharkiv 61085, Ukraine
Pulse Explosive-Driven Electromagnetic Energy Generators

The present paper contains the results from theoretical and experimental investigations into explosive-driven EM energy pulsed generators. It has been suggested that the ionized gas flow, i.e., a plasma jet developing during an explosion, be used. A series of mathematical models describing the processes in a generator at different stages of its operation is devised. The mathematical models are represented as systems of differential equations with variable coefficients in which skin-effects, energy losses caused by shorting on a liner, resistance losses in a coil wire and contacts are taken into account. Conditions arise, under which an oscillatory mode is suppressed and the generator goes over to the aperiodic mode. The temporal and spectral signal characteristics are calculated. The results from the study of plasma antennas excited by a spark-gap generator are given.

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