V.A. Katrich, M.V. Nesterenko, and N.A. Khizhnyak
V. Karazin National University of Kharkov,
4, Svoboda Sq., Kharkov, 61077, Ukraine
Asymptotic Solution of Integral Equation for Magnetic Current in Slot Radiators and Coupling Apertures
On the basis of asymptotic averaging method an approximate analytical solution of the integral equation for a magnetic current in slot radiators and coupling apertures of electrodynamic volumes has been obtained. Formulas have been given for currents and scattering (radiation) characteristics of longitudinal and transverse slots in a broad wall of a rectangular waveguide. A comparison with the results obtained by a numerical method has been carried out.
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P.L. Mladyonov and S.L. Prosvirnin
Institute of Radio Astronomy, National Academy of Sciences of Ukraine
4, Krasnoznamennaya St., Kharkov 61002, Ukraine
Microstrip Double-Periodic Grating of Continuous Curvilinear Metal Strips as a High-Impedance Surface
Frequency dependence of phase reflection coefficient of a microstrip periodic grating of undulated strips is numerically investigated by means of the method of moments. The possibility of using of such structure as a high-impedance surface is shown. The influence of change in shape of the strips and in the parameters of dielectric substrate on the frequency characteristics of the grating is analyzed for the case on normal incidence of a plane electromagnetic wave. The possibility of electronic control of the grating characteristics is demonstrated.
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A.V. Gribovsky and S.L. Prosvirnin
Institute of Radio Astronomy, National Academy of Sciences of Ukraine
4, Krasnoznamennaya St., Kharkov 61002, Ukraine
Frequency-Selective Properties
of a Multi-Element Screen with Rectangular Waveguide Channels
The algorithm have been elaborated for calculation of a generalized wave-scattering matrix by the flat finite-thickness multi-element screen with rectangular waveguide channels. The frequency dependence of reflection factor of a plane electromagnetic wave that is normally impacted upon a two-element screen, have been studied. Wide and narrow walls of rectangular waveguide channels are mutually parallel. The high-Q resonances of total passage and reflection which are similar to "cutoff mode" resonances have uncovered. It is shown that the change in geometrical dimensions of the screen prowids a possibility to obtain the resonances at quite definite frequencies.
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L.V. Kasatkin and V.P. Rukin
'Orion' Research and Development Institute
Mailbox No. 565, 03150 Kyiv, Ukraine
Frequency-Stabilized MM-Wave Semiconductor Sources of Electromagnetic Oscillations
Different lines of attack on the problem of development of MM-wave frequency-stabilized oscillators based on semiconductor diodes and transistors have been investigated. The self-locked excitation, frequency multiplication, and synchronization by subharmonic signal modes of operating are discussed. Relations of frequency similarity, which give the opportunity to estimate the accessible characteristics of frequency stability in wavelength range were estimated. A comparative analysis of stabilizing characteristics have been performed for diode and transistor oscillators of the investigated kinds.
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O.N. Sukhoruchko
A. Usikov Institute of Radio Physics and Electronics,
National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
L-Band Low-Noise Amplifier
The paper presents the experimental research results for a low-noise non-cooled parametric amplifier intended for implementation as an input stage of 60 GHz band receivers. The electrodynamical properties of the oscillation system, in which the coaxial waveguide resonator was used as the idler frequency loop, were studied. The experimental research results for the models of amplifiers, which were executed using the Schottky chip diodes are provided. The gain value was 16 dB within the 1 GHz bandwidth and the electric adjustment range was 6 GHz.
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O.P. Kulagin and V.D. Yeryomka
A. Usikov Institute of Radio Physics and Electronics,
National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Drift-Orbital Resonance in Millimeter Wave Magnetrons
Mechanisms of electron-wave interaction in millimeter wave multiresonator magnetrons are studied. The data obtained by means of the developed theoretical model are compared with the results of experimental study of some magnetrons. Based on the comparison results it was conclude that the probable mechanism of interaction between electron flow and electromagnetic waves in millimeter wave multiresonator magnetron consists in the large-orbit and small-orbit modes of drift-orbital resonance.
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E.I. Zhilin and S.A. Bezverhiy
Military scientific center of space investigations,
6, Svoboda Sq., Kharkov, 61043, Ukraine
Detection of Deterministically Attenuated Signals in Astronomical Photometric Systems
An optimal algorithm of detection of signals against the background of additive noise having Erlang's distribution of a -th order, is suggested. Analytic expressions for likelihood ratio and probabilistic characteristics of detection are obtained. Curves of detection are plotted on the basis of these expressions. A functional diagram of a quasioptimal detector is proposed.
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