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2008, volume 13, № 2

 

 

 

REFLECTION RESONANCES IN A WAVEGUIDE SECTION WITH TWO DIFFERENT HEIGHT POSTS

Kirilenko А., Kulik D., Mospan L., Rud’ L.

154-158

TE10-mode scattering at two different-height rectangular posts, located side by side inside a rectangular waveguide is studied in the paper. A possibility to provide a frequency response with two rejection resonances is revealed. Independent control of the resonance locations is discussed.

 

 

EXCITATION OF THE WHISPERING GALLERY MODES IN THE ANISOTROPIC BALL LOCATED IN FIELD OF THE WAVEGUIDE SOURCE OF RADIATION

Kirichenko A. Ya., Kogut A. E.

159-165

The opportunities and peculiarities of excitation of the whispering gallery modes in the sapphire resonator as the ball located in a field of a waveguide source of radiation are experimentally investigated. Conditions of the most effective excitation of the ball resonator containing single axis of anisotropy are determined.

 

 

MODEL SYNTHESIS OF ENERGY COMPRESSORS

Kuzmitchev I. K., Melezhyk P. M., Pazynin V. L., Sirenko K. Yu., Sirenko Yu. K., Shafalyuk O. S., Velychko L. G.

166-172

A complete electrodynamic model and a synthesis algorithm of energy compressors have been developed for the first time. The theoretical problems have been solved that occur when constructing these structures on the basis of two connected in series axially-symmetrical open waveguide resonators “storage + switch”.

 

 

INVESTIGATION OF THE CM-RADIO WAVE PROPAGATION AT EXISTING EVAPORATION DUCT

Mytsenko I. M.

173-177

The distance dependences of cm-radio wave attenuation factor at existing evaporation duct in different regions of the World Ocean are determined. The empirical dependence between evaporation duct height attenuation factor value for direct field signal at different distances is obtained. The methodical for determination of the main parameter of radio wave propagation path, i.e. attenuation factor, is proposed. Some questions, on this methodical application for diagnosis and prediction of the navigation radar detection range are discussed.

 

 

ABOUT AMPLITUDE FLUCTUATION SPECTRUMS OF GEOSTATIONARY ARTIFICIAL SATELLITE RADIO SIGNALS

Alexeev G. A., Belobrova M. V.

178-184

The work uses the measurement results of amplitude fluctuation frequency spectrums of signals of microwave frequency three-centimeter source, located on the geostationary satellite Hot Bird, at the different troposphere states. The theoretical analysis of influence on the frequency spectrum form of spatial spectrum parameters of heterogeneities, their transport velocities, distance profiles of velocity and troposphere refraction index structural characteristic, is carried out. Possibilities of troposphere radiomonitoring on the frequency spectrums of satellite radio signals is discussed.

 

 

OPTICAL FEATURES OF ATMOSPHERIC AEROSOL OVER BLACK SEA SINCE MAY 2006 TO SEPTEMBER 2007 YEAR

Yakovleva D. V., G. A. Tolkachenko

185-189

Measurements in Sevastopol by the AERONET program of spectral aerosol optical depth (AOD), precipitable water and Angstrom parameter (a) were made. The graphic and histograms of dependence of Angstrom parameter and precipitable water, a and AOD were analyzed, and spectral dependency of AOD was plotted. All measurements presented graphic and in tables. Daily and monthly means of general parameters are described. Results allow to reveal regional particularities of optical features of atmospheric aerosol over Black sea in the Sevastopol region and their temporary variability.

 

 

COMPARATIVE CHARACTERISTIC OF BAND SPECTRUMS OF PERIODIC STRUCTURES, FORMED BY THE LAYERS OF DIFFERENT MATERIALS IN EXTERNAL MAGNETIC FIELD

Bulgakov А. A., Khankina S. I., Shramkova O. V., Yakovenko V. M.

190-199

The comparative analysis of one-dimensional periodic structures formed by two recurring layers: dielectric-dielectric, dielectric-semiconductor, dielectric-semiconductor in a magnetic field, ferrite-ferrite and consecution of quantum wells is realized. For all cases the analytical and numerical investigation of physical peculiarities of enumerated structures is realized. It was shown that investigated peculiarities can be used in practice for the wide spectrum of frequencies from the units of GHz to hundreds of terahertz (from centimeter to X-ray wave length range).

 

 

EVOLUTION AND THE DYNAMICAL STABILIZATION OF MESOSCOPIC DISSIPATIVE STRUCTURES (ROTATING AUTOWAVES) WITH MULTIPLE TOPOLOGICAL CHARGES IN THREE-LEVEL EXCITABLE SYSTEMS

Makovetskii D. N.

200-213

The work is devoted to computer modeling of evolution of mesoscopic dissipative structures (DS), which emerge in three-level excitable systems of the phaser type. The main attention is concentrared on the investigation of the rotating spiral autowaves (RSA), including stable RSA with multiple topological charges. In our computer experimemts, the dimensional phenomena for such the RSA were revealed and investigated in details. The hypersensitivity to initial conditions was demonstrated for a multistable excitable system having spatial attractors in the form of RSA with various higher topological charges. The phenomenon of spatial coexistence of regular and irregular DS during slow transition processes in excitable medium is modeled for the first time (such the phenomenon was observed by us earlier in real experiments on the ruby phaser).

 

 

THICKNESS DETERMINING OF VACUUM EVAPORATED THIN FILMS BY RESONANCE METHOD

Kuzmin A. V., Semenenko V. E., Posuhov A. S., Stervoedov N. G.

214-217

This work deals with the methods of thickness measuring of the coated film by means of a quartz sensor. Nickel films thickness dependence on quartz crystal resonance frequency were obtained and graphically presented.

 

 

TUNNELING ELECTRONS THROUGH THE NON-STATIONARY POTENTIAL BARRIER

Abdulkadyrov D. V., Beletskii N. N.

218-226

Tunneling electrons through a non-stationary tunnel barrier in approximation of small amplitude of a variable electric field is investigated. Conditions of applicability of a mode of one-quantum electronic transitions through a non-stationary potential barrier are determined. Dependence of density of a high-frequency electronic current through a barrier from frequency and the enclosed constant bias voltage of displacement is considered. It is shown, that the active part of density of a high-frequency electronic current can be negative at the abovebarrieric passage electrons through a barrier.

 

 

ABOUT WORK OF A DIFFRACTION RADIATION OSCILLATOR OPERATING ON THE HIGHER SPACE HARMONICS

Korneenkov V. K., Kurin V. G.

227-231

Output characteristics of a diffraction radiation oscillator operating on the higher space harmonics are considered. Comparison of the output power levels and the oscillator inrush currents for operation on the minus first and second space harmonics is given. In particular, the advantages of the oscillator operating on the minus second spatial harmonic in comparison with one operating on the minus first harmonic are shown. Physical interpretation of the high efficiency regimes of the oscillator operation on the higher space harmonics is proposed.

 

 

REGIME OF SELF-OSCILLATIONS IN ABRUPT p-n JUNCTIONS WITH THE CONSTANT REVERSED BIAS

Lukin K. A., Maksymov P. P.

232-238

Equalizations of diffusive-drifting model of the reverse-biased p-n junctions are decided by numeral methods. The regime of self-oscillations in abrupt p-n junctions with the constant reverse-biased is explored. It is shown that equalizations of diffusive-drifting model of the considered p-n junctions are equalizations of mathematical model of the self-oscillation system. The mechanism of origin of self-oscillations is explored. Factors, influencing on frequency, amplitude and spectrum of self-oscillations, are set. The range of frequencies of the reverse-biased p-n junctions from different material is determined.

 

 

MILLIMETER AND SUBMILLIMETER RANGE RECEIVER ON HOT ELECTRONS

Kamenev Yu. E., Sizov F. F., Dobrovolsky V. N.

239-242

A bolometric receiver of the millimeter and submillimeter radiation on hot charge carriers (electrons) with the direct detecting of signals is proposed. The device is functioning at room and lower temperatures at which the biopolar conductivity still exists in it. Operation of the receiver is based on changing the conductivity under the influence of radiation in biopolar plasma of a nallow-slot semiconductor. The experiments which have been carried out demonstrate the possibility to record the radiation by using this receiver at 300 K and the radiation frequencies n = 0,036, 0,039, 0,055, 0,075, 0,89 и 1,58 THz and also at the lower temperatures up to - 80 С.

 

 

CREATION OF PREFERABLE CONDITION FOR EXCITEMENT OF OPERATING MODE IN NOTp-MODE MAGNETRON

Gurko A. A., Yeryomka V. D.

243-248

The reasons for restricting the regions of existing in a magnetic field – oscillations in periodic vane-type cavity oscillating systems of millimeter-wave magnetrons are analyzed. Analytical expressions were derived to describe the relationship between the upper regions. Of the operating mode existence with the oscillatory system parameters and the HF-field structure in the oscillators’ space interaction. A criterion for evaluating the stable operating mode excitation is proposed. This criterion corresponds the magnitude of the relation between the harmonics amplitudes of competing and operating modes on a operating mode synchronization radius.

 

 

APPLICATION OF LOW-TEMPERATURE PHOTORECEIVERS IN QUASI-OPTOCAL INTERFEROMETERS OF TERAHERTZ RANGE

Kiseliov V. K., Kononenko V. K., Kuleshov Ye. M., Nesterov P. K.

249-255

Low-temperature photoreceivers of terahertz range designed for qusi-optical interferometers used for research on high-temperature thermonuclear plasma have been described. The results of phase shifts and polarization plane rotary angles measurements with corresponding them errors are provided. Then electron plasma density and its deviation were obtained from that data.

 

 

REGIONAL ANALYTICAL ALGORITHM FOR SEAWATER INHERENT OPTICAL PROPERTIES RETRIEVING USING SPECTRA OF REFLECTANCE

Korchemkina E. N., Shybanov E. B.

256-262

The method used consists in solving of inverse problem of marine bio-optics on the base of sea reflectance spectrum. Non-standard parameterization of seawater optical properties is realized in iterative algorithm. The condition of reflectance constancy at the wavelength 400 nm is shown to stabilize the algorithm processing. Maps of chlorophyll concentration distribution are plotted for region of South Coast of Crimea. Obtained concentration values are typical for coastal zone of Black Sea in summer period.

 

 

DYNAMICS OF POPULATIONS IN HYDROGEN ATOM UNDER THE ACTION OF ULTRA-SHORT LASER PULSE

Derbov V. L., Teper N. I.

263-270

We present the results of the research of population dynamics in a hydrogen atom driven by a ultra-short laser pulse. The possibility to produce a wave packet of Rydberg states with high values of orbital and magnetic quantum numbers is studied numerically depending on the pulse duration and intensity. To describe the atom-field interaction three models were compared, namely, the one with discrete spectrum states only, the one with resonance bound states and continuum, and the one with non-resonance discrete spectrum states having high values of orbital and magnetic quantum numbers also taken into account. The wave packet formation is simulated by direct numerical solution of the Schrödinger equation using a large number of basis states both of discrete and continuous spectrum. The continuous spectrum is approximated by a large finite number of states separated by a small wavenumber interval. The role of continuum is shown to be principal in the population dynamics and the wave packed formation.

 

 

REDUCTION OF STORED DATA AMOUNT IN NOISE RADAR WITH SPECTRAL PROCESSING

K. А. Lukin, J. A. Shiyan

271-278

Preliminary results of investigation of possibility to reduce the stored data amount in Noise Radar with coherent spectral processing are presented. It is shown that obtaining reliable estimation of envelope and phase of the cross-correlation function of the signal, that is sum of noise reference and radar return, is possible at considerable decreasing of sampling rate. This approach is noted to be more efficient for narrow-band noise signal.

 

 

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