2007, volume 12, ¹ 2
ABSORPTION IN WAVEGUIDE-DIELECTRIC RESONATORS WITH ONE-SIDE RECTANGULAR LEDGE
Rud L.A.
299-305
Features of resonance absorption in dielectric inserts, which one interface has a rectangular ledge and the other is perpendicular to rectangular waveguide walls, are studied. It is found that these resonator structures can provide a strong absorption of the dominant mode power from one port and a strong reflection from the other port. A possibility to use the known qualitative model for determining resonance values of the scattering and absorption coefficients is shown in the case of low-loss inserts. By the results of studying the scattered fields, a treatment of the resonance absorption physical mechanism is proposed.
COMPARATIVE STUDY ON ACCURACY OF FDTD-, GO/PO-, AND IE-BASED ALGORITHMS WITH APPLICATION TO COMPACT INTEGRATED LENSES ANALYSIS
Boriskin A. V., Godi G., Rolland A., Sauleau R., Nosich A. I.
306-318
The aim of the paper is to assess the accuracy and relevance of numerical algorithms based on FDTD and a combination of Geometrical and Physical Optics (GO/PO) principles for the analysis of reduced-size dielectric lenses used in integrated antennas for mm and sub-mm wave applications. As a benchmark solution, we use the Muller’s boundary integral equations (IE) discretized with the trigonometric Galerkin scheme that has guaranteed and fast convergence as well as controllable accuracy. The lens cross-section is chosen typical for practical applications, namely an extended hemiellipse whose eccentricity satisfies the GO focusing condition. The analysis concerns homogeneous lenses made of rexolite, quartz, and silicon with a cross-section size varying between 3 and 20 wavelengths in free space. We consider the problem in 2-D formulation. The lens is excited by either a plane wave or a line current in receiving or emitting modes, respectively. Both E- and H-polarizations are considered. The comparison characteristics are extracted from both near- and far-field analysis.
THE ASYMPTOTIC FORMS OF EXTREME CASES IN DISPERSION PROBLEM ON DIELECTRIC LAYER LOADED WITH SEMI-INFINITE METAL SHIELD
Barkov A. D.
319-327
The method of energy characteristics calculation of the field scattered by two-dimensional metal-dielectric structure when its geometrics and physica parameters equal or approach the critical has been introduced. The resonant modes in low-angled approach for parameter values close to critical have been considered.
POLARIZATION PROPERTIES OF FRACTIONAL FIELDS
Ivakhnychenko M. V.
328-334
Properties of the fractional field, defined as a result of application of fractional curl operator to known solution of some electromagnetic problem, are analyzed. It is shown, that fractional curl is realated with polarization rotation of electromagnetic field. Besides, complex values of the fractional order corresponds to tnasformation of linear polarization to the elliptic one. Fractional curl can be utilized to describe effect of polarization transformation of the field, transmitted through chiral layer. The order of fractional curl is obtained from the chirality parameter, limit values of the fractional order 0 and 1 correspond to dielectric layer and the rotation of linear polarized wave by angle π/2, respectively.
SPACE RESOLUTION AT MEASUREMENT OF COMPONENTS OF ELECTROMAGNETIC FIELDS CLOSE TO EARTH SURFACE
Sugak V. G.
335-340
It is estimated the space resolution of subsurface probing method when the transmitting and receiving dipoles are used. The estimation is based on calculation of TE and TH modes of electromagnetic fields close to earth surface.
SIGNALS OBSERVATION ON (OVER HORIZON) ROUTSDURING ECLIPSE AT MARCH 29 2006
Lutsenko I. V., Lutsenko V. I.
341-344
The measurements of signal levels were carried out on (over horizon) routes during eclipse which was observed at 29.03.06. The hardware complex designed for diagnostics of propagation conditions utilizing TV center signals was used. The signal of transmitting TV center in Belgorod town was in near geometric shadow relatively to receiving point in Kharkov. While measuring the decrease of level of received signal of 6 TV channel analogous to changes of signal level during sunrise and sunset was observed. In addition to complex utilizing VHF band signal transmitted by TV center the ionosphere wave at (mono bounce) propagation SW band signal from radio broadcasting stations was used. The received VHF band signal level changes observed during eclipse were not marked in SW band. However, it is impossible to make unambiguous conclusion about influence of eclipse on signal level on the base of qualitative analysis because similar decreases of signal level were observed some days before the eclipse as well as some days after one.
IMPACT OF IONOSPHERE DAY – NIGHT NON-UNIFORMITY ON AMPLITUDE OF ELF RADIO SIGNAL
Nickolaenko A. P.
345-355
Diurnal amplitude variations were processed of man-made ELF radio wave recorded at the Antarctic station “Bellinshausen”. The propagation path was about 16 Mm long. Average level of the field corresponds to the published data. Diurnal amplitude variations present in the record arise from the day–night non-uniformity of the waveguide. The ambient day level is by 5 – 6 dB lower than that at the ambient night conditions in the vertical electric field component, it is by 4 – 5 dB lower in the horizontal magnetic field. Computational results are presented for the fields in the spherical Earth – ionosphere cavity with the ‘whole day’ and ‘whole night’ ionosphere models taken from literature. Model data contradict to observations. Discrepancy might arise from an inexact value of the model phase velocity of radio waves, which governs the position of interference maxima and minima. Model data match the experiment after the phase velocity is corrected by 10%. Since the ‘whole day’ and the ‘whole night’ ionosphere models do not account for the wave diffraction at the day-night interface, we conclude that more exact modeling is desirable.
CALCULATION OF QUASISTATIC EIGEN-FIELD OF A CHARGE, WHICH MOVES ARBITRARILY IN CYLINDRICAL DRIFT TUBE
Gorbik G. M., Ilyenko K., Yatsenko T. Yu.
356-361
In the Darwin model using the Green’s function method, we found the solutions for quasistatic (quasistationary) vector potential excited in cylindrical drift tube with perfectly conducting walls by arbitrary charge and current densities (e.g., by a charged beam), which satisfy the continuity equation. Green’s functions are expressed as expansion in eigen-functions of the Laplace operator in cylindrical coordinate system with the Dirichlet and Neumann boundary conditions. Having obtained solutions for potentials, we find expressions for the induced magnetic field and relativistic correction to the electric field. Taking into account relativistic corrections to the order of field of radiation, we also found the force acting on the moving point charges of the beam from the induced by itself on the drift tube walls surface charges and currents. A method, which enables one to reduce the problem for vector potential to a system of scalar Poisson equations in cylindrical coordinate system, is proposed.
INFLUENCE OF SOME LIQUIDS ON SEMISPHERE DIELECTRIC RESONATOR SPECTRAL CHARACTERISTICS
Golubnichaya G. V., Kirichenko A. Ya., Maximchuk I. G.
362-366
The influence of the liquids with high level of absorption of electromagnetic waves on electrodynamic characteristics of the open dielectric resonator with the shape of a hemisphere, when the whispering-gallery oscillations of H-and E-types are excited in it in the range of frequencies 34÷38 GHz , has been investigated. It is shown that the perturbation of this resonator from the side of the equatorial cut by the flat surface of liquids leads to the shift of the resonant frequencies about several tens of megahertz and at the decrease in the Q-factor of the oscillations. It is found out that the H-mode is more sensitive to the absorption of the electromagnetic energy. For the optimum a distance between equatorial plane of the resonator and liquid surface must be equal approximately to 3 mm at these frequencies.
STRUCTURE AND PROPERTIES OF ELECTRODEPOSITED CADMIUM SULFIDE FILMS
Li Ò. À., Klochko N. P.
367-371
Cadmium sulfide layers are integral part of the modern solid state photovoltaic devices (PVD) on the base of copper indium diselenide and on the base of cadmium telluride. They play the role of the buffer between the base layer and the transparent electrode. This work is devoted to research of the structure, electrical and optical properties of electrodeposited CdS films. The structural analysis was executed by the method of X-ray diffractometry. For determination of the electrical properties the dark current-voltage characteristics (IVC) of the films were used. Optical properties were investigated by means of spectrophotometry method.
ÑARACTERISTICS OF DISTRIBUTION MAGNETOPLASMA OF WAVES IN RECTANGULAR WAVEGUIDE WITH CROSS-SECTION MAGNETIZED SEMICONDUCTOR
Zamuraev O. A., Tishenko A. S.
372-377
Characteristics of distribution magnetoplasma waves (MPW) in a waveguide containing cross-section magnetized semiconductor are experimentally investigated. Areas of values of a magnetic field in which resonant character of behaviors of a phase constant and factor of attenuation of a wave is observed are determined. The comparative analysis of results of experimental researches and numerical calculations has shown their good coincidence.
OPTIC-ACOUSTIC FOCUSING OF LASER RADIATION ON A WORK SURFACE
Dzjubenko M., Kolpakov S., Kulishenko D., Priyomko O.
378-382
The optic-acoustic method, developed by the authors, of a focusing of laser radiation on a surface of an item is considered at laser dimensional processing. The algorithm of tracking behind a focal point in process engrave is shown and are sharp of a material. The algorithm is based on measurement of the geometric form of a surface of an item. The outcomes of experimental check of the developed method are shown. The practical marketability and technological efficiency is shown it.
ELECTRODYNAMIC SYSTEM FOR DIFFRACTION RADIATION OSCILLATOR WITH RESONANT MATCHING OF DIFFRACTION GRATING
M. Yu. Demchenko, V. S. Miroshnichenko, Yu. V. Svischov, Ye. B. Senkevich
383-388
It is offered the new updating of the open resonant system for the diffraction radiation oscillators (DRO) in which the resonant properties of step heterogeneity in the form of a groove on a mirror for increase of spatial harmonics amplitude of the diffraction grating and decrease of the diffraction losses for basic TEM00q – mode are used. Results of the numerical analysis of modes properties in the open resonator with various depth of a groove are resulted. Results of experimental researches of DRO operating in 4 and 5 millimeter wave range are presented.
EXPERIMENTAL INVESTIGATION OF FREQUANAY SELF-STABILIZATION PHENOMENON IN DIFFACTION RADIATION OSCILLATORS
Korneenkov V. K., Kurin V. G.
389-393
In the open resonators of the explored generators along with modes having one synphase spot of the field, there are observed the occurrence of excitation of higher modes which create a few sport of the field along movement of electronic beam. Electronic beam flying through such chainlet of variations of the field exfoliates on speeds with formation of set of modes of space-charge. It is shown, that disintegration of electronic beam on the set simultaneously of existent modes of space-charge can result in the increase of stability of frequency of generator in one case, in other - to excitation of generator in the multifrequency mode. Communication of stability of frequency of generator with stability of disordering between velocity of electrons and phase velocity of synchronous wave is set.
RESONANCE TUNNELLING CATHODE FOR GUNN DIODE
Î. V. Botsula, E. D. Prokhorov, I. P. Storozhenko
394-400
A Gunn diode with resonance tunnelling cathode have being conceded. The current-voltage characteristics diode have two region of negative difference conductivity that can be used for high frequency oscillation. The oscillation efficiencies for both region have being determined. The particulars of diode operation has been considered. The factors to be influence on oscillations has been analysed.
QUANTUM EFFICIENCY OF THE INGAAS/GAAS RESONANT CAVITY ENHANCED PHOTODETECTOR FOR THE ULTRASHORT OPTICAL CONNECTION
Gryshchenko S. V., Dyomin A. A., Lysak V. V., Petrov S. I.
401-407
We present a theoretical analysis on the quantum efficiency of a resonant cavity enhanced (RCE) InGaAs/GaAs p-i-n detector for the ultrashort optical connections. The quantum efficiency (QE) under resonant condition has been calculated. The math model includes physical parameters of photodetector and takes into account wavelength, reflecting availability of mirrors and optical absorption in all photodetector layers. QE dependence from the top mirror reflectivity coefficient based on Al0,65Ga0,35As/GaAs was obtained. Magnitude of reflectivity coefficient of the top mirror in dependence of different physical parameters was found.
SURFACE RELIEF DETERMINATION BY CLINOMETRIC METHOD IN THE CASE OF REDUNDANCY AND DEFICIENCY OF THE INITIAL DATA
Dulova I. A., Kornienko Yu. V., Skuratovskiy S. I.
408-415
The method of determining both the surface relief from the slope field and the slope field from initial images has been formulated in the present paper. It is shown that the problem can be successfully solved when using a correct statistical approach in the case of overdetermined and underdetermined system of equations that relates relief to initial data. The possibilities of the method are illustrated by computerized models.
DETERMINATION OF COMPOSITION BLEND OF LOOSE SUBSTANCE WITH USE OF THE DI-ELECTROMETRIC METHOD
Krivenko E. V., Kirichenko A. Ya., Lutsenko V. I.
416-420
The Q-factors of characteristic oscillations of axial-flaky structure that consist of dielectric layer is parallel to faceplate of partially shielded half-disk dielectric resonators are investigated. We ascertained that bringing into the resonator field parallel to its lateral face at some aiming distance of dielectric example leads to resonator eigenfrequencies and Q-factor changing the more, the higher the real and imaginary parts of investigated material permittivity. Influence of dielectric component composition, its thickness and aiming distance on resonance frequency and Q-factor is investigated. The dependences of frequency and electronic tuning steepness of self-excited oscillator on basis of Gunn diode stabilized of axially flaky structure on dielectric component composition and moisture are obtained.
DISK DIELECTRIC RESONATOR FOR THE LOW-TEMPERATURE MAGNETORESONANCE INVESTIGATION IN MILLIMETER AND SUBMILLIMETER BANDS OF WAVELENGTHS
Derkach V. N., Bagmut T. V., Golovashchenko Ð. V., Korzh V. G., Nedukh S. V., Tarapov S. I.
421-425
The description of electron spin resonance experiments in millimeter wave range by using the resonant cell as a high quality disk dielectric resonator on whispering gallery modes is resulted. The value of quality factor Q=30000−38000 is achieved with ESR mark in the field of working temperatures about Ò = 4,2 K.
RESULTS OF THE RESEARCHES OF WEAKENING OF THE ENERGY OF ELECTROMAGNETIC WAVES BY OPTICALLY OPAQUE BARRIERS
Vyazmitinov I. A., Y. I. Myroshnychenko, O. V. Sytnik
426-434
In work the results of experimental researches of losses of electromagnetic waves are examined in optically opaque environments from point of the basic requirements to descriptions detection of people after the optically opaque obstacles. As the objects of research the standards of building constructions and materials which can be the most credible obstacles at man-caused catastrophes were chosen. Dependences of fading of radio waves are explored on frequency. Possibility of reception of the reflected electromagnetic signals is shown from living movable objects being after concrete ceilings. The requirements are discussed to condition of experiments and method of their conducting. Authenticity of results is motivated.
EHF DIELECTROMETRY METHOD FOR CONTROLING OF POND POLLUTION WITH SURFACE–ACTIVE MATERIALS
Shchegoleva T. Yu., Parshikova T. V., Krasov P. S., Bryuzginova N. V., Masyuk B. R., Ruzhelnik E. A.
435-438
By using EHF dielectrometry method data, which characterize parameters of hydrated encirclements of the microalgae culture were taken. These results allow us to analyze the molecular mechanisms of reaction of native cellular algae suspension. Surface-active materials (KSAM) in concentration which not exceed maximum permissible concentration (MPC) were taken as an acting substance.
MODELING OF A 2,4 GHZ INTEGRATED CLASS E POWER AMPLIFIER
Makarov D. G., Krizhanovskii V. V.
439-443
A 2,4 GHz integrated class-E power amplifier implemented in 0,18-μm CMOS technology was designed and simulated. Using differential topology and cascode output stage the amplifier delivers 0,47 W of output power in 50-Ohm load with PAE of 60% with supply voltage of 1,2 V.
MODELLING OF IMPULSIVE PHOTOMULTIPLIER ON BASIS OF PN-I-PN STRUCTURE WITH AVALANCHES P-N JUNCTIONS
Lukin K. A., Cerdeira H. A., Maksymov P. P.
444-450
An impulsive photomultiplier is designed on the basis of avalanches pn-i-pn structures with the internal (avalanche-cascade) amplification. An amplification coefficient, fast-acting and noise of avalanche multiplication are expected. It is shown that photomultipliers on the basis of pn-i-pn structures have a high amplification coefficient, low threshold of sensitiveness on a current and more reliable in work as compared to avalanches photodiodes.
QUASIOPTICAL POLARIZATION ATTENUATORS IN THE TERAHERTZ FREQUENCY RANGE
Bezborodov V. I., Kiseliov V. K., Kuleshov Ye. M., Yanovsky M. S.
451-455
The loss of quality of grating polarizers operating in terahertz frequency range results in the limitations of inserted attenuation interval indicated by direct reading scale of polarization attenuator and occurrence of parasitic orthogonally polarized signal on the attenuator output. The comparison of different modifications of polarization attenuators including transmitting and reflective polarizers has allowed to make conclusion of merits of attenuators including transmitting polarizers. The examples of the attenuators realized on the basis of hollow dielectric and metal-dielectric waveguides are presented.