1. 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. 3-7
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 axial-symmetric pattern, a wide polarization pattern and a low level of side lobes.
2. Features of the forest radio emissi
L.M. Atroshenko, K.P. Gaikovich, N.N. Gorobets, V.N. Gorobets
radio emission, a forest
Vestnik KhNU ¹806 Pages. 8-13
Dielectric permeability of sheet plates of deciduous breeds of trees, dependence of the level of own wood signal from its projective covering, temperature distinctions, diffraction of radiowaves and their plural reflections in a crone of trees are investigated.
3. THE H10 WAVE SCATTARING BY THE THIN VARIABLE RADIUS IMPEDANCE VIBRATOR IN A
Nesterenko, E.Y. Belogurov, V.A. Katrich, V.I Kijko
impedance vibrator, biconical vibrator, distributed surface impedance, rectangular waveguide, the method of induced electromotive forces
Vestnik KhNU ¹806 Pages. 14-17
The problem of the fundamental wave scattering by the thin variable radius impedance vibrator arbitrary situated in a rectangular waveguide was solved. Calculations were carried out and energetic characteristics of such structures were plotted
4. RECTANGULAR WAVEGUIDE M.V.
millimeter range, parametric amplifier, oscillatory system, band of the reinforcement, relative noise temperature
Vestnik KhNU ¹806 Pages. 18-21
Semiconductor two-stage parametric amplifiers have been developed to be used in the input circuits of communication and navigation systems in the short-part of millimeter wave band. In the 60 to 65 GHz range, the gain is no worse than 15 dB at -3 dB level in 1 to 1.6 GHz bandpass. The noise temperature is no higher than 500K when the quasi-optical IMPATT oscillator is in using as the pumping generator.
5. Arbitrary falling of wave on grate with by ànisotropic layer
A.I.Adonina, R.R.Naumov, A.I.Sljusarev
grate, magnetodielectric, stream of power, method of Riman-Gilbert, anisotropic, resonator
Vestnik KhNU ¹806 Pages. 22-28
A decision set the problem is conducted for Å and Í pour, proper two subsystems into which the system of equalizations of Maxwell is divided for anisotropic environments. The mixed field (in the case of the arbitrary falling of wave) is determined as a sum of two types pour. Integral descriptions are from the decision of the reduced endless systems of linear algebraic equalizations, got the method of task of Riman-Gilbert. The analysis of the graphs, partly resulted in work, allows to set influencing of parameters of structure and angles of incidence of wave on an anomaly in the dissipated field for every concrete case, and also to suppose and to confirm physical reasons of existence of anomalies a numeral account, as resonances of own waves in the opened resonator which is design the explored structure.
6. Way of transformation of the patterns of reception antennas
A.A. Sorokin, A.F Sorokin, O.V. Sokolova, R.N. Zaluzhniy, N.N. Gorobets
miñrowaves, antennas, pattern, Frenel zones
Vestnik KhNU ¹806 Pages. 29-32
the expedient of management by the shape of directional diagrams with the help of a fragmentation of Frenel zones is offered. Measuring the shape of a pattern diagram of the horn and spiral antennas are carried out. Peak allocations a builder of a field in short-range, medial and long-range bands for different frequency range are received and analyzed. By results of experiments intensity, a corner, radius for long-range and short-range bands is constructed 3D images.
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. 33-39
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.
8. The influence of a dispersion and losses to the interaction of impulse signal with the model of the biological tissues
O.N. Zheryobkina, O.V. Kazanskiy
impulse signal, a biological tissue, time domain, flatlayer dielectric, dispersion
Vestnik KhNU ¹806 Pages. 40-43
In this paper the interaction of the impulse signal with biological tissues on an example of the flatlayer dielectric that models consecutive layers a skin, fat, muscle tissue is investigated. In this model, it is taken into account dispersion of the dielectric permeability and losses in a medium. The calculation program is received in result. It accounts the space-time characteristics of the reflected and past signals for layers of the flatlayer dielectric with parameters of biological tissues. Influence of values of the dielectric permeability and angle of incidence on the characteristics of past and scattered signals also is considered.
9. Mode basis method for open dielectric waveguide
A. Butrym, M Legenkiy
mode basis method; open waveguide, eigenmode
Vestnik KhNU ¹806 Pages. 44-47
The Mode Basis Method construction for the rectangular waveguide with the dielectric insertion when one of the walls of the waveguide is removed to the infinity is considered. Spectrum division into the discrete (surface waves) and continuous parts is analyzed. The range of the continuous change of the spectrum parameter, the presence of the accumulation point and the finite numbers of the discrete modes is revealed. The formulae of the field expansion over the eigenmode of the structure are obtained.
10. Thermo equilibrium and differential capacity of p+-n junction
p+- n junction, distribution of potential
Vestnik KhNU ¹806 Pages. 48-53
The accurate distribution of field and potential in the region of abrupt p+- n junction under thermodynamic equilibrium is obtaned. The formula of p+- n junction width with any relation of mobile charge carrier magnitude and ion donors of n-region is obtained. The dependence of p+- n junction differential capacity upon out voltage, which does not need numerary methods is obtained. It was shown, that under direct and reverse switching of p+- n junction the dependence of capacity upon voltage is more complicated than for p- n junction in the depletion mode.
11. Thermo equilibrium state of p+-p junction
p+-p junction, distribution of potential
Vestnik KhNU ¹806 Pages. 54-58
The thermo equilibrium state of p+-p junction with surface charge of p+-region was investigated. The distribution of field and potential in the region of such junction is describing by Poisson's equation with un-known charge distribution on coordinate. The solution method of this equation allowing to obtain precise distribution of field and potential on coordinate was proposed. The formula for width of p+-p junction with any ratio of mobile charge carriers and charge of ion-acceptors in p-region was obtained.
12. CALCULATION AND MEASURING OF IMPEDANCE OF IMPATT-DIODE IN MILLIMETR WAVE
A.V. Arkhipov, V.T. Plaksiy, I.K. Kuzmichev, E.D. Prokhorov, A.V. Dydchenko, D.P. Chuechkov
millimeter wave range, impedance, IMPATT diode, conductance, susceptance
Vestnik KhNU ¹806 Pages. 59-64
The calculated and experimental results of the impedance of the impact avalanche transit-time (IMPATT) diode for the 8 millimeter wavelength range have been presented. The dependences of the IMPATT diode impedance as a function of the normalized amplitude î Ã the fundamental current harmonic of the p-n junction and frequency have been calculated and measured. The apparatus and measuring method of the conductance and susceptance of the IMPATT diode has been developed
13. HARMONIC GENERATION BY IMPACT IONIZATION IN CaN LSA DIOD
O.V. Botsula, D.V. Pavlenko, E.D. Prokhorov
LSA diodes, generation efficiency, nitrides, drift velocity, harmonics
Vestnik KhNU ¹806 Pages. 65-69
In this work an impact ionization in LSA diodes on basis of GaN is considered. Analytical calculation of typical times of passing of a number of the physical processes determining properties of the oscillator, and limitings imposed by them on frequency properties of the diode is submitted. It is shown, that at developing impact ionization in LSA diodes, according to the diffusive theory, the considered compounds are perspective for manufacturing LSA diodes for work in sm and mm - ranges (electrical pressure over threshold 3 … 5 times, at an efficiency up to 11 … 13 %). The results of calculation of efficiency of oscillators on basis of GaN LSA diodes are given at their work in modes on a base frequency and at a harmonic generation.
14. Identification and localization of radar impulses buried in noise
A. G. Tyzhnenko, Y. V. Ryeznik
radar, pulse, identification, localization, low SNR
Vestnik KhNU ¹806 Pages. 70-74
Statistical method identification and localization of radar impulses buried in noise is addressed. To this end, the correlation coefficient between carrier samples measured in the extremal points and analogous set of points of received signal is proposed to implement. Such measurements for receiving signal need to be done at least by one tenth of the half period of the carrier. Because of very simple algorithm proposed, such measurements do not lead to heavy computational burden. To decrease identification and localization errors for given signal to noise ratio (SNR) one needs to increase the number of measurements points, and hence, the pulse width. To prevent this issue, one can increase the carrier frequency. In general, the method accuracy increases with the carrier frequency. The method proposed permits theoretically to identify with fidelity impulses buried in noise for SNR lower than -30 dB.
15. Theory of the millimeter waves o-type clinotron amplifier
E.N. Odarenko, A.A. Shmat'ko
nonlinear multidimensional theory, clinotron amplifier, electrons settling
Vestnik KhNU ¹806 Pages. 75-81
Nonresonant amplifier O-type system with inclined focusing field is considered. Theoretical investigation is carried out within the framework of the beam-wave interaction multidimensional model. Input signal power, focusing field magnetic induction value and electrons settling on the electrodynamical system surface are taking into account
16. Spatial and temporal features of the midlatitude total electron content
I. G. Zakharov
total electron content, dual-frequency Doppler shift measurements, planetary waves
Vestnik KhNU ¹806 Pages. 82-86
Experimental study of the latitudinal and diurnal variations in the total electron content over Eastern Europe are present. The dual-frequency Doppler shift measurements from navigation satellites and incoherent scatter radar (ISR) data are used The ISR data were collected near Kharkiv city (49.6oN, 36.6oE), and the dual-frequency signals from navigation satellites in circular polar orbits at the altitude of about 1000 km were received at the Kharkiv V. Karazin National University Radiophysical Observatory (49.6oN, 36.3oE). The calculated total electron content maps span the 35o – 65oN geographic latitude range and the 24-hour local time range. These maps and other data represent all known features of diurnal and latitudinal total electron content variations at middle and subauroral latitudes, and in particular, they represent the local latitudinal maximum at 50oN geographic latitude in total electron content. The results obtained also indicate that tidal and planetary-scale waves act to noticeably modify the temporal and spatial variability of TEC, including that under quiet conditions.
17. Selection of the high-order modes in the waveguide resonator by means a phase-shifting 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 high-order transverse modes, a phase filter, Fourier optics, selection
Vestnik KhNU ¹806 Pages. 87-91
The method of the space Fourier-filtration for selective excitation of separated high-order 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 phase-shifting mirrors for shaping of the high-order transverse modes in the laser resonators containing waveguides and open parts are proposed
18. QUEST AND CREATION OF NOVEL ACTIVE MEDIA FOR DYE LASERS IN IRE NAS OF UKRAINE
laser dye, molecular structure, spectrum, fluorescence, quantum yield, lasing efficiency, photostability
Vestnik KhNU ¹806 Pages. 92-98
Numerous studies of novel active media for dye lasers fulfilled in IRE NAS of Ukraine are generalized in present review. Peculiarities of spectral, fluorescence and lasing characteristics of some laser dye classes for visible region of the spectrum have been analysed. A special attention is focused upon effects of structure of the dye molecule and its solvent environment on these characteristics. The outlook of development for dye-doped active media has been discussed
19. Application of the digital holographic interference microscope for investigation of thin films
D.N. Tishko, T.V. Tishko, V.P.Titar, Yu. A. Zadneprovskiy, A.S. Kuprin, I.A.Zgoda
digital holographic interference microscope, three-dimensional images, vacuum-arc method, thin AlN films
Vestnik KhNU ¹806 Pages. 99-102
For the first time the digital holographic interference microscope (DHIM) was used for investigation of thin films on transparent substrates. Three-dimensional images of AlN of thin films, deposited on acryl substrates by the vacuum-arc method have been obtained, their thicknesses have been measured. It has been shown that the DHIM can be successfully used for film surface quality checking, thickness and film damages parameters measurement.
20. Increase of free volume 0f the aip abundant in the water by the millimeter waves of low intensity
B. G. Yemets
electromagnetic waves, air bubbles, field of temperature, convection
Vestnik KhNU ¹806 Pages. 103-106
Using an NMR technique the volume growth of the free ("bubble") air contained in water caused by low-intense electromagnetic waves is obtained. This change is caused by rectified diffusion of the dissolved air mass into bubbles. The increase in the free air may occure only under those conditions when there is no convection in the liquid, i. e. in the case of irradiating by means of low-intense waves.
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