2003, volume 8, ¹ 3
MODELING OF A PERIODICAL MICROSTRIP ARRAY ON A CYLINDRICAL SURFACE
Svezhentsev A.E.
319-324
An excitation problem for a phased periodical array of a finite number of patches N placed on a dielectric substrate surrounding a circular metal cylinder is discussed. As an excitation N plane waves which fall in the same phase on grating elements are chosen. An integral equation to find a surface current density on a patch surface is obtained. An efficient algorithm to calculate a kernel of the integral equation (Green’s function) is proposed. The main idea of the approach is to extract the Green’s function singularity and a surface wave contribution in an explicit form. As a consequence, the rest of the Green’s function can be effectively calculated numerically.
TWO-HEMIDISK QUASI-OPTICAL DIELECTRIC RESONATORS
Lavrinovich A.A., Cherpak N.T., Shaforost E.N.
325-330
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 K-band for the resonators with one- and two-side displacement of the dielectric samples in the slot (1) symmetric and (2) asymmetric 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.
ELECTROMAGNETIC DIFFRACTION ON BRANCHED METALLING SHELLS
Grimalski O.V., Lapovok A.J.
331-337
A numerical model of electromagnetic field for thin metallic shells with complex branched geometry is considered. This provides a computer technology for modeling both patch and wire radiating structures of arbitrary topology. Numerical results (RCS, input impedance) compared against measurements for various scatterers are presented.
WIND INFLUENCE ON THE SEA RADAR BACK SCATTERING INTENSITY
Gutnik V.G., Sharapov L.I., Kulemin G.P., Efimov V.B.
338-345
The calculated estimates for sea surface back scattering intensity and intensity of drop – spray fraction are presented in this paper obtained for centimeter and millimeter bands of radiowaves and for wind velocities up to 40 meter per second. Comparative analysis and comparison with experimental data is carried out. It is shown that back scattering from drop-spray fraction forming as result of sea wave breaking plays more and more part for wavelength shortening and velocity increasing of near sea wind.
THE MULTIPATH PROPAGATION EFFECTS ON CLUTTER MAP MODELING AT
MILLIMETER RADIOWAVES
Kulemin G.P., Tarnavsky E.V.
346-353
The features of modeling and the derivation of millimeter wave multipath propagation in troposphere near land surface for radar observation map of targets are considered. The technique of modeling for real terrain are applied taking into consideration terrain roughness and vegetation. The results of modeling are described.
REFLECTION INFLUENCE FROM THE SEA SURFACE ON CONDITIONS OF DISTANT TROPOSPHERIC PROPAGATION
Mytsenko I.M., Zatserklanaya A.V., Khalamejda D.D.
354-356
The reflection influence from an interface in the line-of-sight coverage on the specific effective scattering area and total troposphere volume involving in the creation of scattered radiation has been estimated. To estimate the change of the specific effective scattering area we have used the Villars-Weiskopf theory. The approximate value of the propagation factor for the meter and decimeter radio-wave bands has been obtained. The results of the calculation and experiment have been compared.
DIURNAL VARIATIONS OF PEAK FREQUENCIES OF SCHUMANN RESONANCE IN THE CAVITY EARTH - ANISOTROPIC IONOSPHERE
Nickolaenko A.P., Rabinowicz L.M.
357-365
The results are presented of Schumann resonance modeling in the Earth – ionosphere cavity with gyrotropic upper wall. Influence of the anisotropy of the lower ionosphere is shown to produce not only the difference in the current values of peak frequencies of two orthogonal components of horizontal magnetic field, but also provides distinct diurnal variations of these frequencies. The ‘hedgehog’ model of the geomagnetic field was used, and the equatorial vertical electric dipole served as the field source.
EXCITATION OF SURFACE ELECTROMAGNETIC PULSES BY ELECTRON BUNCHES INTERSECTING A METAL -DIELECTRIC - SEMICONDUCTOR STRUCTURE
Averkov Yu.O., Yakovenko V.M.
366-373
Transition radiation of surface electromagnetic pulses by a nonrelativistic electron bunch intersecting a metal-dielectric-semiconductor structure is investigated. The bunch is rotation ellipsoid with uniform charge density and moves along the normal to the structure on the side of the metal. The dissipation of radiation energy is taken into account. It has been shown that the spectrum density of transition radiation of surface waves has the shape of a sequence of decreasing oscillations. The appearance of maximums of the spectrum density is conditioned by some resonant relations between the width of the dielectric layer, the bunch dimensions, the radiation wavelength and the Van Kampen’s wavelength. It has been found that there are dimensions of the width of the dielectric layer such that the radiation energy and the coefficient of efficiency of radiation have the maximum. This coefficient equals to the ratio of the radiation energy to the total kinetic energy of bunch electrons.
THE CONFORMAL MAPPING MATHOD FOR ANALYSIS OF HIGH FREQUENCY ELECTRO-MAGNETIC FIELDS OF SLOW-WAVE STRUCTURES. CH. III. THE CONCRETE SLOW-WAVE SYSTEMS ANALYSIS
M.V. Mil`cho
374-385
The examples of the analysis of concrete slow-wave structures (the comb with screen and the double comb) are presented. Dispersion relations are derived and amplitudes of field space harmonics are calculated. The field distribution near the slow-wave structures surface is analysis. The effect of the contrary wave on the metal electrode surface is revealed.
CALCULATION OF THE SPECTRAL-TEMPORAL CHARACTERISTICS OF RADIATION OF TUNABLE DYE LASERS WITH FLASHLAMP PUMPING
Shevchenko V.V.
386-392
The problem of evolution of the spectral characteristics of a radiation of flashlamp-pumped dye lasers is considered with allowance for of inhomogeneous spectral distribution of cross-section of radiation and absorption. The dependence of a lasing wavelength on parameters of an active medium and resonator is found. There was shown, that inhomogeneous distribution of the triplet-triplet absorption in a selective resonator can result in a modification not only spectral, but also temporary characteristics of pulsed radiation of dye lasers.
THE INVARIANT TRANSFORMATIONS IN IDENTIFICATION THEORY
Sytnik O.V.
393-403
In work the generalized approach to the decision of problems of identification of a condition of natural environments and objects with use of invariant models is considered. Ways and a technique of synthesis of models with use of the tensor analysis are considered. As a basis of such approach the opportunity of representation of physical object serves in its every possible displays in relation to an environment as some complex system. Each element of this system is compared to beforehand described class. And the equations of researched complex system are under construction, using all parities between streams, sizes and the processes proceeding in system, including such which appear superfluous, superfluous at synthesis of models by classical methods. In a basis of a method of construction of functional subsystems of objectiveed focus models the approach based on the transformation connecting space of signals and space of spectra of parameters of object is fixed. The linear or nonlinear case is considered and by lines of consecutive transformations of coordinates of initial space the configuration of model which provides a minimum of losses at decision making concerning object is received.
METHOD OF RANDOM SOURCES’ SIMULATION
S.A. Krivenko
404-409
In this work a method of simulation which can be realized by microprocessor is presented. Block diagram of simulator includes the following clauses: pseudo random noise generator, regular pulse excitation, long term synthesis filter, short term synthesis filter, post-processing.
TECHNIQUE OF THE QUICK SUMMATION OF POWERS OF THE FAR INTERACTION BETWEEN PARTICLES IN N-BODY PROBLEM
Shevchenko I.N., Krizhanovsky V.G.
410-419
We report on efficient calculation method
of power of interaction in N-body problem, which allows for time 
produce the analysis of behaviour of such ensembles of
particles, for which use direct summation method requires unbelievably big
calculation time. In contrast with the other methods of the similar purpose he
possesses the advantage, which are important at modeling of the collective
processes in semiconductor device by method of the particles.
QQUASI-OPTICAL INTERFEROMETERS WITH ENHANCED PHASE SENSITIVITY
Nesterov P.K.
420-425
Quasi-optical interferometers designed for determination of electronic plasma concentration ne by means of sub-millimeter wave probing and measurement of phase shift j of wave transmitted through plasma are described. The interferometers has been carried out on the basis of a hollow dielectric beamguide and radio metering quasi-optical devices. The schemes suggested allow to increase the accuracy of ne determination when j measured by known interferometers is equal to units or tens of degrees.
MILLIMETER-WAVE PLANAR FREQUENCY MULTIPLIER
Ermak G.P., Kochergin V.P., Kuprijanov P.V.
426-428
A design and results of an experimental research of a planar frequency multiplier based on a planar Schottky diode is described. The circuit of the multiplier is executed on a teflon substrate and established in a metal case having input and output waveguides. The all microstrip and slotlines components fabticated with photoway. The doubler provides the input frequency band of 52-60 GHz and the output band of 104-120 GHz. At the input power of 20 mW the maximum output power is 600 microwatt.
THE LOOP ANTENNA FOR RECEIVING UWB PULSE SIGNALS
Ogurtsova T.N., Pochanin G.P., Kholod P.V.
429-437
A simple method of determination of loop antenna parameters intended to receive ultrawideband (UWB) signals is presented in the given work. The influence of the loop sizes and load resistance on the broadbandness and sensitivity of the UWB receiving loop antenna has been analyzed. The dependence of the current amplitude at the antenna output on its geometry has been obtained. The influence of the quantity of elements of the multielement loop antenna and its sizes on the directional and distortion pattern of the received signal waveform has been analyzed.
HELICAL ANTENNA WITH TRANSVERSAL RADIATION
Melyanovsky P.A., Popov I.V.
439-442
Symmetric vibrator, shoulders of it are made as a spiral with small diameter and small step, provided considerable shortness is considered. Resonant properties of such vibrator are compared with resonant properties of linier vibrator.