1. Radiation from dualmode circular waveguide excited by dominant and higherorder modes simultaneously A.V. Shishkova, N.N. Gorobets microwaves, multimode waveguide, diffraction, higherorder modes, Weinstein rigorous technique, WienerHopf technique, radiation pattern. Vestnik KhNU ¹712 Pages. 5661
On the basis of Weinstein rigorous solution to the problem of electromagnetic mode diffraction at an openended circular waveguide the characteristics of radiation from multimode waveguides excited by H_{11} dominant mode and. higherorder modes (E_{01}, and H_{01}) simultaneously are calculated and analyzed. The calculation of radiation from waveguide with dual mode excitation is carried out in the whole observation space and in wide frequency bandwidth, taking into account the higherorder mode transformation and currents leaking on the external surface of a waveguide.
2. Absorption of electromagnetic energy of dipole antenna of double layer dielectric sphere V.V. Radchenko Wave absorption, double layer dielectric sphere, perfectly conducting spherical screen, radial dielectric dipole, dual series equations, method of analytical regularization Vestnik KhNU ¹712 Pages. 6266
Considered the problem of electromagnetic energy absorption by double layer sphere, which the simplified model of human head protected by the helmet with the dipole antenna. This investigation is interesting due to control of energy absorption in sensible parts of human head tissues. The problem is solved by method analytical regularization, which reduces the problem to the system of linear equations of Fredholm second kind which provides guaranteed convergence. Basic absorption characteristics are obtained and comparison of protection effectiveness for different sizes helmets are made
3. Integral representation of green function in parallelplate and rectangular waveguide, and in resonator as well V.A. Katrich, F.S. Novokhatsky Waveguides, Green function, fundamental solution, radial function, elliptical teta function, image method, calculus of residues, integral transformation, grating, formal variative Vestnik KhNU ¹712 Pages. 6770
The known results connected with Green function representation by elliptical thetafunction are generalized. New representations of Green function for some widely used types of waveguides are obtained. Earlier, these Green functions are presented either in form of series with nonuniform convergence or in form of integrals containing Hancel functions, which are reduced to asymptotic expressions in far zone. On this work integral representations of Green functions are obtained for Cases where the quadrature formula exists. The method of analytical continuation with parameter is applied
4. Radioacoustic wind sounding of the atmosphere bo un dat y layer: history of the development and perspectives Y. N. Ulyanov, V. I. Vetrov, N. G. Maksimova radioacoustic, Wind, sounding, atmosphere, boundary layer, profile, adaptation Vestnik KhNU ¹756 Pages. 2732
The article is devoted to the potentialities of the method of radioacoustic sounding when monitoring the vertical structure of the wind in the atmosphere boundary layer (ABL). A review of methods for radioacoustic measurements of the horizontal wind velocity and direction is based on the developments of the authors and their experience in this field as well as on the world experience. It is emphasized that the radioacoustic method for sounding the wind in ABL is perspective, since for the RAS equipment, there are not characteristic neither high levels of the electromagnetic pollution of the environment like for radiolocation wind profilers  radars nor loss of the serviceability at ligh levels of the ambient acoustic noise like for acoustic wind profilers  sodars.
5. SELECTIVE excitation of the HIGHorder MODES IN THE waveguide quasioptical RESONATOR A.V. Volodenko, O.V. Gurin, A.V. Degtyarev, V.A. Maslov, V.A. Svich, A.N. Topkov Waveguide quasioptical resonator, excitation of the highorder transverse modes, an amplitude filter, Fourier optics Vestnik KhNU ¹756 Pages. 123131
The method of the space Fourierfiltration for selective excitation of separated highorder transverse modes in the waveguide quasioptical resonator with a high discrimination degree of undesirable modes is proposed and realized. It is carried out numerical study of characteristics of some the lowest on loss transverse modes of the dielectric and metal resonators of the submillimeter laser from geometric sizes of reflectors and parameters of the space filter on the nonuniform mirror. Configurations of the amplitudestepped mirrors for shaping the highorder transverse modes in the laser resonators containing waveguides and open parts are proposed
6. Directed and polarization characteristics of the aperture of the circular waveguide with impedance flange N.N. Gorobets, V.M. Dakhov, I.V. Gorbach microwave, antennas, Waveguides, polarization, pattern Vestnik KhNU ¹806 Pages. 37
The amplitude and polarization patterns of the radiator in the form of the aperture of circular waveguide with impedance flange, excited by the dominant wave, have been measured by the method of the indicator antenna with polarization plane rotation. It is shown that such radiators have an axialsymmetric pattern, a wide polarization pattern and a low level of side lobes.
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7. Resonance phenomena occurring as a thin refractive cylinder diffracts the hertzian wave Yu. I. Grebenyuk, N. G. Kokodiy, Khe Shi diffraction, thin cylinder, refractive index, scattering, absorption, Weakening, resonance Vestnik KhNU ¹806 Pages. 3339
On the basis of solutions to the wave equation, the efficiency of dispersing, absorbing, and weakening the electromagnetic field that a thin cylinder with a large refractive index diffracts has been estimated. The transverse and longitudinal distribution of the electromagnetic field inside and outside of the cylinder has been calculated. The resonance is found to increase the intensity of both the electromagnetic wave field inside the cylinder and the scattered wave outside. Inside the cylinder at resonance, a wave propagating along its surface arises, and under some conditions, a wave propagating through the cylinder is also generated. As the refractive index is increased, the wave tracks the cylinder surface more closely, and its intensity is progressively enhanced.
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8. Selection of the highorder modes in the waveguide resonator by means a phaseshifting mirror A.V. Volodenko, O.V. Gurin, A.V. Degtyarev, V.A. Maslov, V.A. Svich, A.N. Topkov Waveguide quasioptical resonator, excitation of the highorder transverse modes, a phase filter, Fourier optics, selection Vestnik KhNU ¹806 Pages. 8791
The method of the space Fourierfiltration for selective excitation of separated highorder modes in the metal waveguide quasioptical resonator with a high discrimination degree of undesirable modes is realized. It is carried out numerical study of characteristics of some the lowest on loss transverse modes for the metal resonators of the submillimeter laser from resonator geometric sizes and parameters of the phase filter on the nonuniform mirror. Configurations of the phaseshifting mirrors for shaping of the highorder transverse modes in the laser resonators containing waveguides and open parts are proposed
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9. Near electromagnetic field of combined waveguideslot radiators in matter S.L. Berdnik, V.A. Katrich, M.V. Nesterenko, S.V. Pshenichnaya rectangular waveguide, Waveguideslot radiator, material medium, hyperthermia, Galerkin's method Vestnik KhNU ¹834 Pages. 8588
The problem about the electromagnetic waves radiation into the homogeneous isotropic medium by the system of combined waveguideslot radiators in the broad wall of a rectangular waveguide has been solved in a rigorous selfconsistent formulation. The spatial distribution of the near field intensity in the halfinfinite material medium with the electrophysical parameters, corresponding to some man's tissues, has been investigated
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10. Longitudinal slot in a rectangular waveguide with dielectric layer parallel to wide walls A.A.Liakhovskyi slot, microwaves, Waveguide, dielectric, admittance, scattering parameters. Vestnik KhNU ¹883 Pages. 5966
The longitudinal slot is cut in wide wall of rectangular waveguide with threelayer dielectric filling which parallel to wide wall is considered. The excitation problem is solved with modified eigen waves method. As eigen waves of the LM and LE modes ar
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11. Own magnon polariton surface modes in the open passage resonator with gyromagnetic medium Mizernik V.N., Shmat'ko A.A. magnon polatiton oscillations, the ferrite resonator, a junction of waveguides, the through passage open resonator, Wavegaide inhomogeneity, area of connection, system of the linear algebraic equations. Vestnik KhNU ¹966 Pages. 3136
The problem about owen modes of the open reentrant resonator partially filled is theoretically solved by gyrotropic ferrite medium and existence magnon polatiton surface (ÌPS) mods with tall concentration of a field on boundary line of the ferrite resonator is established. The every possible combined regimes of existence of superficial and volumetric fashions are analysed, dependences of their resonant frequencies on material parameters of medium and geometrical sizes of the resonator and a ferrite layer are certain.
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12. slot, microwaves, Waveguide, dielectric, admittance, scattering parameters Vestnik KhNU ¹883 Pages. 5966
The problem of a longitudinal slot radiation is cut in wide wall of rectangular waveguide with threelayer dielectric filling which parallel to wide wall of a waveguide was solved. The excitation problem is solved with modified eigen waves method. As eigen waves of the LM and LE modes are chosen. The field in the source region includes the potential functions as well. The scattering parameters and resonance properties of slot are investigated. The scattering parameters calculated are in a good agreement with experimental data.
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13.
Waveguide resonator, misalignment of the mirrors, terahertz range, energy losses, mode composition, polarization Vestnik KhNU ¹983 Pages. 1822
The influence of the curvature of the spherical mirror for metallic waveguide resonator of submillimeter laser (lambda = 0.4326 mm) on energy losses and the mode composition of radiation is investigated. It is shown that the presence of quadratic phase aberrations in the mirrors of the waveguide cavity with an increase of its Fresnel number at monotonically decreasing of the energy losses for fundamental asymmetric mode TE11q due to a decrease of waveguide losses also leads to their substantial nonperiodic oscillation.
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14.
Wave equation, exact solutions, localized waves, Bateman solution, general astigmatism. Vestnik KhNU ¹983 Pages. 7783
A new class of exact nonharmonic in time solutions of 3D wave equation is established. This class is a generalization of the known complexified relatively undistorted Batemantype solution, involving an arbitrary function, waveform. Argument of this function is much similar to that which appears in general astigmatic paraxial Gaussian beam. Special choices of the waveform allow general astigmatic beamlike and packetlike waves with Gaussiantype localization in space and time.
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15.
slot, Waveguide, dielectric, admittance, scattering parameters, slotwaveguide array. Vestnik KhNU ¹927 Pages. 5964
The scattering problem of a longitudinal slot system is cut in wide wall of rectangular waveguide with threelayer dielectric filling which parallel to wide wall of a waveguide was solved. The scattering parameters and gain of linear slottedwaveguide array are investigated in range of frequency. The gain optimization and synthesis of linear slottedwaveguide array were carried out using a genetic algorithm. The obtained gain weakly depends from frequency.
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16.
Waveletanalysis, continuous wavelet transform, dynamic energogram, space radio physics, powerful nonstationary disturbance sources. Vestnik KhNU ¹927 Pages. 96102
Development and improvement of methods of timefrequency analysis of signals with continuous wavelet transform usage were proposed. The new method consists in the simultaneous analysis of wavelet spectrum and dynamic energograms of the continuous wavelet transform. Using the example of analysis of real nonstationary, nonlinear and ultra wideband signals and processes in space radio physics problems, in particular, using the analysis of effects, caused by the powerful, nonstationary action, the dynamic energogram method effectiveness was shown.
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17.
Wigner transform, Cohen’s transform class, space radio physics, signal processing, powerful nonstationary disturbance sources, volcano explosion, solar eruption. Vestnik KhNU ¹927 Pages. 8995
Being a member of Cohen’s class of integral transforms, nonlinear integral Wigner transform for analysis of the real signals and processes in geospace radar methods is applied. At samples of the May 18, 1980, explosion of Mount St. Hellens and the December 5, 2006, very strong Xray solar eruption, the effectiveness of Wigner transform application to the processing of nonstationary, nonlinear, fractal and ultrawideband signals and processes in problems of space radio physics, in particular, to the investigations of processes, accompanying the effects of powerful nonstationary disturbance sources was shown.
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