Yu. K. Sirenko
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Exact 'Absorbing' Conditions in Outer Initial Boundary-Value Problems
of the Electrodynamics of Nonsinusoidal Waves.
Part 4: Pulse Antennas
The exact 'absorbing' conditions are constructed, which allow one to replace the 'open' initial boundary-value
problems inherent in the radiation theory of nonsinusoidal electromagnetic waves by the equivalent 'closed' problems.
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A.I. Vyazmitinova and Yu.K. Sirenko
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Near Fields from Nonsinusoidal Wave Sources: A Numerical Analysis
Numerical results are presented of the analysis of interaction effects between pulsed electromagnetic fields
and objects representing prototypes of practically important beam-shaping structures (BSS). Several effects
have been considered that should be taken into account in the synthesis of radiators of nonsinusoidal waves
and other systems oriented toward analysis of solitary electromagnetic pulses.
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O.V. Grimalsky and A.Ya. Lapovok*
Kostroma state technological university, Kostroma, Russia
*A.N. Krylov Central research institute, St. Peterburg, Russia
Diffraction of Electromagnetic Waves by Metallic Shells Having a Ramified Geometry
Numerical model is considered of electromagnetic field excited by thin metallic shells having complicated ramified geometry.
Approach is suggested for development of computational models using surface and linear radiating structures
(plates, shells and rods) with arbitrary topology. Numerical results such as scattering characteristics and input impedance
for a number of scatterers are presented.
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A.A. Kirilenko and L.P. Mospan
Usikov Institute of Radio Physics and Electronics National Academy of Sciences of Ukraine
12. Academician Proscura St.. Kharkov 61085. Ukraine
Rejection Irises as E-Plane Extracted Pole Filter Sections
The paper presents results of synthesis and optimization of a bandpass filter made of longitudinal metal strips,
with additional rejection poles in its frequency response. Rejection poles are introduced by a rejection waveguide
section, which is either a single or a double multi-slot rejection iris. The key improvements in the bandpass
filter performance are the increased rejection rate and the frequency selectivity. Numerical data are presented for the
1-5% bandwidth X- and Ku-range E-plane extracted pole (Chebyshev) filters.
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A.A. Kirilenko, D.Y. Kulik, V.I. Tkachenko, and S.F. Kulishenko
Usikov Institute of Radio Physics and Electronics National Academy of Sciences of Ukraine
12. Academician Proscura St.. Kharkov 61085. Ukraine
Generalization of the Partial Domain Method for the Waveguide
Tee-Junctions with Metallic Inserts in the Interior Domain
In this paper, we suggest a modified mode-matching method that is applied to compute the S-matrices of ̉-junctions
of rectangular waveguides with various inserts in the coupling region. We consider in detail how to compute
an H-plane tee-junction with a separating plate in the straight arm, which is frequently used to divide linearly-polarized signals.
This algorithm provides a good computation efficiency excluding the regions near to the irregular points corresponding
to the eigen oscillations of the coupling domain with metallized walls.
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A. A. Kirilenko, D. Yu. Kulik, S.L. Senkevich, and V. I. Tkachenko
Usikov Institute of Radio Physics and Electronics National Academy of Sciences of Ukraine
12. Academician Proscura St.. Kharkov 61085. Ukraine
Extending “the Shorted Port Method” for Calculation of S-Matrices, Using Reduced Numerical Models
New essential details of “the port reflection coefficient method”, providing reconstruction of
a multiport S-matrix by the ones for the same multiport, having several shorted ports, were considered.
The ways for calculation of multimode matrix and for elimination of transmission matrix sign doubts have been put forward.
The main result consists in a minimization of the calculation errors by using a special choice of intermediate model geometries.
The method under consideration is of particular assistance at solving the analysis and design problems of complicated multiports
with coordinate boundaries by the generalized mode-matching technique.
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A.A. Lavrinovich, N.T. Cherpak, and E.N. Shaforost
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Two-Hemidisk Quasi-Optical Dielectric Resonators
A new modification of quasi-optical dielectric resonator in the form of two dielectric hemidisks with
a diametric slot between them in which another dielectric can be placed is investigated.
In hemidisks the conditions for propagation of the whispering gallery mode waves is kept.
The results of the frequency spectrum measurements in Ka-band for the resonators with one- and two-side
displacement of the dielectric samples in the slot 1) symmetric one and 2) asymmetric one with radial conductor reflector)
are presented and discussed. Evolution of resonator frequency spectrum in going from travelling wave regime to standing wave regime is followed.
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V.N. Manzhos, S.N. Pshenichnykh, Ye.B. Krylov, and Yu.À. Poponin
Kharkov Military University
Bivariant Direction-Finding of Noise Signal Sources with
a Ring Phased Antenna Array Using Keypone and Music Methods
Methods of the bivariant direction finding of noise signal sources with a ring phased antenna array are considered.
Comparative analysis of the direction-finding results with the algorithms of the spatial Keypone and
MUSIC superresolution is performed.
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V.B. Razskazovsky and Yu.A. Pedenko
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Modeling Millimeter and Centimeter Wavelength
Fields over the Sea in the Analysis of Elevation Angle Estimation Methods for Low-Flying Aerial Targets
The paper touches on the problem of modeling millimeter and centimeter-wavelength fields over a rough sea surface
in the case of grazing field incidence. Based on the analysis of published data, a field model has been developed,
applicable to analyzing radar methods of elevation angle estimation for low-flying targets. An approach to selecting
model parameters is justified, including the range distribution of diffuse reflections in the case of surface patch shadowing
by wave crests. A correction method is suggested for the specific bistatic scattering ratio, such that estimates
of the diffuse reflection factors can be reconciled with real measured data. The field model developed was used
in computer simulation of elevation angle measurements by radar systems. The simulated results
are close to those obtained in real sea measurements.
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A.P. Nickolaenko and L.M. Rabinowicz
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Diurnal Variations of Peak Frequencies of Schumann Resonance in the Gyrotripic Earth - Anisotropic Cavity
The results are presented of Schumann resonance modeling in the Earth - ionosphere cavity with anisotropic upper wall.
Gyrotropy of the plasma in the lower ionosphere separates the instant values of peak frequencies of two orthogonal
horizontal components of magnetic field. It also causes the distinct difference in their diurnal variations.
The results of the paper were obtained in the 'hedgehog' model of the geomagnetic field for an equatorial vertical electric dipole source.
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A.M. Gokov and O.F. Tyrnov
V. Karazin National University of Kharkov,
4, Svoboda Sq., Kharkov, 61077, Ukraine
Middle Latitude Ionospheric D-Region Responses
to Solar Events as Investigated by Partial Reflection Technique
Using a partial reflection technique, there were experimentally investigated the middle latitude ionospheric D-region responses
to X-ray radio-frequency radiation (XRA), optical flares (FLA) on the Sun, to geomagnetic sudden storm commencements (ssc)
for an appearing shock solar front at the time of solar flares, and to events of solar protons (spe) precipitating into the
Earth ionosphere. In characteristic time intervals after the phenomena mentioned above, characteristic changes
in parameters of the partial reflection signals, radio noise and electron density were found to occur with characteristic
durations of about tens of minutes. There is given a possible physical interpretation of the middle latitude
D-region responses for each type of the phenomena: on the basis of the experimental data on the electron density
changes, the estimations of change rate of the D-region ionization were made, and calculations
of the precipitating electron and proton flow parameters were carried out.
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Yu.V. Goncharenko and F.V. Kivva
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Evaluation of Size of the Atmospheric Aerosol Particles in the Reflecting Layers
Occurring after Intense Solar Flares
The hypothesis for the effect of aerosol layers emerging after intense solar flares on variations
in the temperature profile of lower and middle atmosphere is considered. Estimated aerosol particle
size does not contradict the water aerosol physics and approximately corresponds to the maximum of the
Dermidzhyan H-distribution for altitude and stratospheric aerosols.
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G.P. Kulemin and Ye.V. Tarnavsky
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Spatial Statistical Characteristics of Soil
The spatial statistical characteristics of the soil surface have been analyzed.
They are required not only to provide an adequate insight into the remotely sensed data
on the ground surfaces, which are obtained from aerospace carriers but also to construct appropriate models.
It is shown that these characteristics might be separately described by means of in-situ measurements and topographic maps.
Spatial roughness spectra can be represented in a fractal form. The distribution of local surface slope angles is found
to be sufficiently close to the normal (Gaussian) law while the height distribution of roughnesses cannot be properly
approximated by some theoretical law.
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V.A. Malakhov, G.I.Doroshenko, O.I. Belous*, S.P.Sirenko*, and A.I.Fisun*
Kharkov Medical Academy of Post-Graduate Education,
Kharkov, Korchagintsev, 58
*A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Comparative Study into Effeciency of Treating the Initial Stage
of Cerebral Ischemia with Low-Intensity Millimeter and Centimeter Electromagnetic Waves
A comparative study into the effect of low-intensity electromagnetic radiation of SHF and EHF
bands on the clinical pattern and cerebral hemodynamics of the patients with cerebral ischemia in initial stage has been undertaken.
The treatment has been virtually the equal in efficiency for the irradiation with either SHF or EHF electromagnetic fields.
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G.I. Klochko, A.I. Logvinenko, and O.V. Sytnik
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkov 61085, Ukraine
Noninvasive Estimation of Temperature Gradient of Inner Layers of Living Tissues by the Ultrasonic Method
Paper is devoted to a problem of the equipment development for the remote sensing of temperature gradient
of inner layers of objects which are inaccessible in the contact methods of measurement.
The idea of the analysis of ultrasonic fluctuation reflected from the inner inhomogeneity environments
and restoration of a structure of distribution speed of pressure along a sounding beam is used as the basis for this method.
Analysis of the possibility of realization of the remote temperature sensing is carried out on the basis of a method
of the boundary integrated equations. The measurement technique is offered on the basis of a differential-phase method
of an estimation of speed of distribution of the reflected signals. Requirements to the equipment and algorithms
of the reflected signal processing are formulated. A difference-phase method is used as the heart of a distribution speed of the reflected signals.
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