2010, volume 15, № 3
RADIATION OF the complex electrical and magnetic dipoles
In the Presence of a perfectly conducting DISK
M. V. Balaban, A. I. Nosich
4-10
An efficient analytically-numerical scheme for solving the given time-harmonic electromagnetic wave scattering by a perfectly electrically conducting (PEC) zero-thickness disk is presented. It is based on the dual integral equations formulation and the method of analytical regularization which is applied for their solution. Complex electric and magnetic dipoles which are located on the axis of the disk and complex Huygens element are considered as sources of the incident field. Total field radiation pattern and normalized radiated power are presented for the various incident fields and geometries.
ELECTROMAGNETIC WAVE SCATTERING BY CURVED SCREEN WITN FINITE THICKNESS
I. O. Sukharevsky, S. V. Nechitaylo, D. D. Ivanchenko, P. N. Melezhik
11-16
The numerical method for solution of problem of electro-magnetic wave scattering by arbitrary curved screen with finite thickness is suggested. Proposed method is based on solution of electric field integral equation. The results of calculation of scattering characteristics for spherical screen and for screen that is not the body of revolution are presented. The results for spherical screen are compared with experimental ones.
MODELING OF THE PLANE ELECTROMAGNETIC WAVE SCATTERING BY A DIELECTRIC CYLINDER
E. A. Velichko, A. P. Nickolaenko
17-24
The numerical model was constructed of the plane wave diffraction by a circular cylinder based on the classic solution. This allowed for calculating the spatial distribution of the scattered and the complete fields of the E- and H-polarizations of incident radio wave. The spatial distributions of the full field amplitude were compared in the cases of metallic and dielectric cylinders. Two polarizations and two frequencies were treated. Angular patterns of the scattered and complete fields were constructed. A phenomenon is discussed, which is similar to the Brewsters’ effect pertinent to the plane electromagnetic wave incident at the plane dielectric interface. Similar effect appears at the cylindrical boundary within a small range of incident angle.
FORM BIREFRINGENCE CHARACTERISTICS OF DIELECTRIC SUBWAVELENGTH GRATINGS IN TERAHERTZ REGION
D. I. Kuleshov, I. V. Scherbatko, M. S. Yanovskiy
25-29
Stable Rigorous Coupled Wave Analysis method employed for modeling of refraction and birefringence effective coefficients for dielectric subwavelength grids. As an example, the broadband quarter- and half-wave differential phase sections were calculated on the basis of dielectric grating in the range of 1,7…2,55 mm wavelength.
ON RELAY-RACE INTERACTION OF STRIP ELECTRON BEAM WITH TRAVELLING
WAVE IN THE PRESENCE OF TRANSVERSE MAGNETIC FIELD
G. A. Alexeev, L. V. Stulova
30-34
Distributed (relay-race) interaction between the wide strip electron beam and the travelling space field harmonic in the presence of the transverse static magnetic field in the drift space is studied theoretically. Designing of microwave devices of travelling wave klystron type is analyzed. These devices use spatial (distributed) modulation of the electron velocity followed by the electron dynamic focusing in the drift space.
ELECTRODYNAMIC MODEL OF THE OPEN RESONATOR WITH A DIELECTRIC LAYER
A. Y. Popkov
35-39
The work is devoted to constructing an approximate mathematical model and theoretical study of the cavity resonator with a dielectrical layer. Such system supports high-Q axially-symmetrical oscillations. In this case the system is equivalent to a hemispherical open resonator with a segment of one-side shorted oversized circular waveguide. The dependences of the frequency of natural oscillations of the thickness and permittivity of dielectric layer are calculated. It is shown that the dependences have quasiperiodic behaviour.
Ways of the sufficient broadbandness increase of a «pure» wave conversion on the cascade of strip diaphragms in planar waveguide
V. V. Shcherbak
40-45
We consider a problem of an optimization of cascades of periodical strip diaphragms providing an effective power transmission of the wave ТЕ1,0 into ТЕn,0 or between higher ТЕp,0 and ТЕM,0 (at the flat-topped band characteristic). We sufficiently have enlarged a working frequency-band of such devices. For this purpose we organize (by the essential dissimilarity of distances between diaphragms) mode coupling ТЕp,0 and ТЕM,0 at minimality of longitudinal beatings 1 and 1 for them (in different resonators) instead of 2 and 1. The dielectric insertions and other constructive innovations are used also.
AXIALLY-SYMMETRIC EIGENOSCILLATIONS OF AN OPEN RESONATOR WITH A SPHERICAL METAL INSERTION
Yu. V. Svishchov
46-50
Numerical experiment results on properties of axially-symmetric eigenoscillations of a spherical-mirror open resonator in the case of a spherical metal insertion are discussed. An effect has been discovered that the eigenoscillation quality increases by several orders of the magnitude due to the insertion of a certain radius sphere.
ERRORS OF DIRECTION-FINDING OF RADIANT ON AZIMUTH AT INFLUENCE OF DIFFRACTION OF RADIO WAVES ON BORDER OF OBSTACLE
V. B. Razskazovskyy, Yu. F. Logvinov
51-57
In Fresnel diffraction approximation on a semiplane the azimuthal errors of direction-finding of microwave radiant are investigated by numerical method. Influence on the azimuthal errors of smooth and rough edge of screen is analyzed at its different orientations on a route.
ON THE POSSIBILITY OF USING GPS SATELLITE RADIATION AT SMALL ANGLES FOR SEA ROUGHNESS DIAGNOSTICS
V. B. Sinitsky
58-64
The results of field measurements of signals of GPS satellites setting over the sea surface are presented. The temporal variability of the diffuse component of the sea-scattered signal and the association of this component with the wind speed in the measurement zone are shown.
THE FEATURES OF USAGE THE MUSIC ALGORITHM FOR AN ELEVATION ANGLE MEASUREMENT OF LOW-LEVEL TARGETS OVER ROUGH SEA SURFACE
Yu. A. Pedenko
65-70
The performance of the MUSIC algorithm for measuring elevation angle of the low-level target over rough sea surface in environment describable with the strong diffuse reflections was executed by computer simulation. It is established that the greatest action on errors value produce a part of diffuse reflections coming from closely approximating to radar zone of «glistening surface». For the purpose of reduction of errors value it is offered to antennas axis which are a part of a array, to establish under a positive angle to an interfacial area. Thus radiation pattern of antennas should suppress as much as possible diffuse signals coming from a near zone, providing sufficient receive level for the signal arriving from the target. Characteristics of measurement errors of elevation angle in various phase difference between direct and specular signal in the centre of a reception antenna array and at various axis angles above the horizon are analysed.
INFLUENCE OF DIELECTRIC RELAXATION ON THE RESULTS OF CONTACTLESS RESISTIVITY MEASUREMENT OF SEMIINSULATING CdZnTe CRYSTALS
S. L. Abashin, V. K. Komar, D. P. Nalyvaiko, S. V. Oleynick, V. M. Puzikov, M. A. Rom, S. V. Sulima, O. N. Chugai
71-77
The difference in values of electric resistivity r measured in both stationary and alternating electric fields was established for Сd1–xZnxTe crystals (х = 0,12…0,16). It was shown that this difference is related to energy dissipation of alternating electric field caused by dielectric relaxation (DR). To evaluate the contribution of DR in r, it was proposed to employ a relaxation oscillator frequency distribution function, which can be found from the frequency dependence of crystal permittivity.
Influence of signal delay on magnetization dynamics of two coupled spin-torque nano-oscillators
O. V. Prokopenko, R. V. Verba
78-82
The possibility of synchronous generation in array of interacting spin-torque nano-oscillators (STNO) is considered. The influence of signal delay on STNOs synchronization was shown. The semianalytical method for calculation characteristics of synchronous generation of greatly non isochronous self-excited oscillators was developed. The dependencies of phase-locking bandwidth on system parameters were obtained and analyzed for optimum in case of two coupled STNOs.
3D MOTION OF ELECTRONS IN KLYNOTRON OSCILATOR
CH. 1. NUMERICAL METHOD ANALYSIS
M. V. Mil’cho
83-91
The three-dimensional electron movements in the klynotron-type oscillator are analyzed by computer calculation. The interaction between the electrons and longitudinal and transverse high frequency field components is taken into account. The exact electrodynamics solution for the comb field description is used. The field singularity on the comb surface is taken into consideration. The electron-field energy transfer is examined. In chapter 1: the physical model, the H.F. fields calculation method and the computer integration method are described. In chapter 2: the results of the real klynotrons computerized analysis are presented.
STEPPED FREQUENCY CONTINUANCE WAVE GROUND PENETRATING RADAR (SFCW GPR) INTENDED FOR DETECTING AND RECOGNIZING SMALL BURIED OBJECTS
V. G. Sugak, A. V. Bukin, E. M. Vasilyeva, O. V. Ovchinkin, Yu. A. Pedenko, Yu. S. Silaev, E. V. Tarnavskiy, V. N. Bormotov, A. V. Sugak
92-97
Stepped Frequency Continuance Wave Ground Penetrating Radar (SFCW GPR) intended for detecting and recognizing small buried objects is described. The homodyne structure of the SFCW GPR in which a wideband demodulatore is applied for measuring quadrature signal components. The advantage of the GPR is application of developed slot magnetic antenna that allows the cross polarized components of reflected signals to be measured by using an electronically commutated slots of the antenna.