Telecommunications and Radio Engineering, 59(7, 8, & 9)

A.D. Barkov
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Application of the Factorization Method to the Problem of Wave Diffraction by Two-Dimensional Planar Metal-Dielectric Structures

The functional singularities appearing in the problem of plane wave diffraction treated in the factorization technique are analyzed. The diffracting structure is a homogeneous dielectric layer containing a perfectly conducting half-plane. The fundamental mode amplitude is analyzed in dependence on the problem parameters.

A.A. Aleksandrova and Yu.N. Aleaksandrov
Kharkov National University of Radio Engineering and Electronics,
14, Lenin Ave, Kharkov, 61166, Ukraine
On the Wave Propagation and Transformation in Magnetohydrodynamic Medium

Linear transformation of magnetohydrodynamic waves on surface of discontinuity is analyzed based on previously obtained fundamental solution of system of linear differential equations of magnetic hydrodynamics in moving medium and on extinction theorem in magnetohydrodynamic interpretation.

A.I. Kozar
Kharkov National University of Radio Engineering and Electronics,
14, Lenin Ave, Kharkov, 61166, Ukraine
Figurate Numbers (Arithmetic Progression) and Electromagnetic Wave Scattering on Spatial Lattices of Resonant Magnetodielectric Spheres

Considered is the problem of electromagnetic wave scattering on complex spatial lattices of special kind, consisting of resonant-size spheres whose spatial distribution is controlled by figurate numbers. Expressions for the scattered fields are derived.

A.G. Nerukh
Kharkov National University of Radio Engineering and Electronics,
14, Lenin Ave, Kharkov, 61166, Ukraine
Fresnel Formulae in the Time Domain

A space-time representation of Fresnel's formulae is obtained which makes it possible to describe the interaction of complex space-time electromagnetic signals with a planar dielectric interface and includes the case when the interface itself is non-stationary, for example, it evolves into existence at a certain point of time. Such description has been made by using integral equations.

V.V. Radchenko
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Radiation from a Spherical-Circular Microstrip Patch Antenna Excited by a Slot

A dipole antenna on the surface of a partially screened layered dielectric sphere is simulated. Application of the analytical regularization technique, based on explicitly solving an Abelian integral equation, has allowed obtaining an infinite set of linear algebraic second-kind Fredholm equations. Basic characteristics of the antenna have been obtained.

Ye.A. Yatsenko and N.M. Yatsenko
V. Karazin National University of Kharkov,
4, Svoboda Sq., Kharkov, 61077, Ukraine
Excitation of Mutually Perpendicular Dipoles

Problem on excitation of currents and on determination of radiation fields in far-field wave-zone for system of two ideal linear dipoles situated in one plane perpendicularly to each other, without mutual intersection, is solved by integral equation method. Formulae are obtained for currents in each antenna, taking into account their mutual influence. Fields and radiation power in far-field zone are determined.

P.L. Tokarskiy
Kharkov National University of Radio Engineering and Electronics,
14, Lenin Ave, Kharkov, 61166, Ukraine
Mutual Impedances between Horizontal Electric Dipoles at the Interface between Two Mediums

Interaction of two horizontal electrical dipoles placed on the interface between two media, one of them having finite conductivity, is considered. The expression involving the integral and asymptotic terms is obtained for mutual impedance of two parallel dipoles. Extracting the asymptotic term from the general expression allows to reach a quick convergence of the integration. Mutual impedance between n parallel dipoles as a function of the distance between them are presented for different conductances of medium.

I.M. Mytsenko, A.V. Zatserlyanaya, and D.D. Khalameyda
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Influence of Reflections from Sea Surface on Long-Distance Tropospheric Scattering

An influence of reflection from the sea-atmosphere boundary in the line-of-sight coverage on the specific effective scattering cross-section (ESCS) and the total troposphere volume being involved in scattered radiation is estimated. To determine the variations in the ESCS the Villars-Weiskopf theory has been employed. An approximate value of the propagation factor for the VHF- and UHF-band waves has been derived. A comparison between the calculations and experimental data is made.

V.G.Gutnik¹, L.I.Sharapov¹, G.P. Kulemin², and V.B.Yefimov³
¹Radioastronomy Institute, National Academy of Sciences of Ukraine
4, Krasnoznamyonnaya St., 61002 Kharkov, Ukraine
²A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., 61085 Kharkov, Ukraine
³A. I. Kalmykov Center of Radiophysical Earth Sounding, National Academy of Sciences and National Aerospace Agency of Ukraine
12, Academician Proskura St., 61085 Kharkov, Ukraine
Wind Influence on the Sea Radar Backscattering Intensity:Computer-Calculated Estimation and Comparison with Experiment

Calculated estimation of the EM wave back-scattering intensity induced by the sea surface and drop-spry fraction are presented in paper. Evaluation is obtained in centimeter and millimeter wave bands for wind velocities up to 40 meter per second. Comparative analysis and comparison with experimental data is carried out. It is shown that backscattering from drop - spray fraction forming as result of sea wave breaking, plays more and more part with wavelength shortening and velocity increasing of near sea wind.

V.M. Kartashov
Kharkov National University of Radio Engineering and Electronics,
14, Lenin Ave, Kharkov, 61166, Ukraine
Signal scattering functions of atmospheric sounding systems

The signal scattering function which allows with relative ease to determine the essential informational features of systems of both radio acoustic and acoustic atmospheric sounding, was defined. Its special features were studied.

I.M. Mytsenko and S.I. Homenko
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Distance Dependence of the Damping Factor for Metric and Decimetric Waves in an Inversion Layer Condition

Influence of reflections from sea surface on shape of a spatial dependence of the radio-wave damping factor and, consequently, possibility of over-th-horizon location of the surface objects at definite distances in presence of inversion layers has been shown.

E.V. Rogozkhin, V.A. Antonova, and L.Ya. Emelyanov
Kharkov National University of Radio Engineering and Electronics,
14, Lenin Ave, Kharkov, 61166, Ukraine
Improvement in the Antenna Commutator Characteristics of Incoherent Scatter Radars

The possibilities to perfect the antenna commutator characteristics are discussed for incoherent scatter radars. The additional circuits were demonstrated to have properties like chouse of decoupling between transmitted and received channels of radar.

V.V. Shevchenko
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Analysis of Spectral and Temporal Characteristics of Radiation from Flashlamp-Pumped Tunable Dye Lasers

The problem of developing spectral and power characteristics of radiation from pulsed Hashlamp-pumped dye lasers is considered with allowance for the nonuniform spectral distribution of the radiation and absorption cross-sections. The lasing wavelength has been determined in dependence on parameters of the active medium and cavity. As has been shown, the nonuniform distribution of the triplet-triplet absorption in the selective resonant cavity can lead to changes not only of spectral but also of temporal characteristics of the radiated pulses.

S.V. Nickolaev and V.V. Pozhar
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Extending the Tuning Range of Dye Lasers through Optimization of Active Element and Cavity Parameters

The generation range of flashtube-pumped dye lasers is investigated in dependence on the spectral response of the cavity's output mirror and length of the active element. As has been found from theoretical calculations and experiment, a maximum range of adjustment can be obtained, at a fixed pump level, through the use of mirrors with a nonlinear spectral response function. The nonlinear function can be properly selected for any specific set of the active element parameters and any level of the pumping power.

M.M. Bykov, M.I. Dzyubenko^*, and I.M. Rudchenko
Kharkov National University of Radio Engineering and Electronics,
14, Lenin Ave, Kharkov, 61166, Ukraine
^*A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Simulation of the Pulse Mode of a Laser with Phototropic Q-Switch in the Conditions of Resonant Interaction of Thermal Noise with the Modulating Medium Substance

The modeling of the pulse operating mode of a laser with phototropic Q-switch in the conditions of thermal noise processes in the modulator has been carried out. The dependences of pulse radiation characteristics on the value and dispersion of noise have been analyzed.

D.N. Makovetskii
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Saturation of Stationary Inversion States in a Three-Level Traveling-Wave Quantum Amplifier with Bistable Resonator Pumping

The inversion states of a saturated three-level traveling-wave quantum paramagnetic amplifier have been investigated under conditions of bistable resonator pumping. The equations of motion for the vectorial order parameter have been obtained using adiabatic elimination of fast variables. These equations are a generalization of the scalar two-level Drummond model for the case of a three-level quantum active system. Isolated branches of the constant of inversion have been found from stationary solutions of equations for the vectorial order parameter. A analysis of bifurcations in the saturated quantum amplifier with bistable pumping has been represented with full details.

V.M. Kuzmichev and S.V. Pogorelov^*
V. Karazin National University of Kharkov,
4, Svoboda Sq., Kharkov, 61077, Ukraine ^*National University of Pharmacy,
35, Pushkinskaja St., Kharkov, 61002, Ukraine
Measuring of Gaussian Beam Laser Pulse Parameters with Nonlinear Thin-Wire Bolometers

A measuring technique of coordinates of a distribution center, root-mean square radius of a beam, module of an angle of the linear polarization and radiation pulse energy of Gaussian laser beam with thin-wire platinum bolometers with a nonlinear transformation characteristic is justified. Analysis of errors of measured results is carried out. Two identical thin-wire bolometers are placed in some distance from the beam centre within its cross-section parallel each other in a vertical direction and two bolometers of similar nature are placed in horizontal direction. Bolometers are placed in the inclines of intensity distribution of a Gaussian beam outside of the main radiation energy.

O.V. Gurin, V.A. Maslov, V.A. Svich, A.N. Topkov, and Ye.V. Fursova
V. Karazin National University of Kharkov,
4, Svoboda Sq., Kharkov, 61077, Ukraine
Formation of a Beam with a Uniform Intensity Distribution of Radiation in a Waveguide Quasi-Optical Resonator with an Amplitude-Stepped Mirror

The method of obtaining non-Gaussian light beams with a uniform intensity profile in the waveguide quasi-optical resonator (WQR) is described. It is based on the self-imaging properties of multimode waveguides and using the non-uniform mirror with the discretely distributed absorbing sections. The theoretical model and calculation algorithm of the low-loss Fourier-mode properties with uniform intensity distribution at the output mirror of WQR are developed with application of the eigenmodes and the Fourier-optics methods. The conditions of the Fourier-mode existence and stability of its characteristics are established by changing the resonator geometry and its non-uniform mirror parameters.

V.I. Beloglazov, А.N. Dovbnya, and P.I. Mospan^*
National Scientific Center Kharkov Institute of Physics and Technology , Kharkov, Ukraine
^*A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
The Indicator of Oscillation Frequency for a Powerful Pulse Active Oscillator

The paper presents the device description which destined for control of oscillation frequency that is generated by powerful pulse klystron active oscillator, going in composition of linear electrons accelerator. In the device a transformation principle of explored frequency with consequent modulation is used. The frequency indicator enables one to control significance of explored generator frequency f_ent = 2797 MHz with 25 kHz accuracy, going in routines continuous and pulsive, as during lasting exploitation, so and inside of every impulse. Experience of quinquennial exploitation bore out that such a device is unchanged one for linear electron accelerator exploitation.

N.D. Koshevoi, M.V. Cehovski, and V.A. Gordiyenko
National Aerospace University (Kharkov Aviation Institute),
17, Chkalov St., Kharkov, 61070, Ukraine
Design of the Thickness Meters for Dielectric Coating

Several variants of solution of a design problem of arrangements for the measurement of dielectric coating thickness as well as prospects of their application and ways of improvement are proposed.

A.D. Yegorov, V.A. Yegorov, S.A. Yegorov, and E.V. Zdor
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
The Photometry of Emission Optical Spectrum by Line Image Sensors

The present paper deals with the issues relating to the correctness of using the rectangular gem of smoothing in the determination of the analytical parameters of spectral lines on the emission spectrometers having multi-cell photodetectors. The techniques for the photometry of optical spectra recorded through the use of photographic carriers and multi-cell photodetectors are shown to offer some essential differences. Use of the rectangular gem of smoothing with an indefinite phase and half-width of a spectral line may lead both to the loss of photometry accuracy and deterioration of resolution. The dependence of the value of the component of an error in determining the amplitude magnitude of the light flux of the spectral line maximum upon its half-width and the position with respect photodetector pixels is considered. The method of the correct solution to the problem is discussed.