Begell House Inc.
Telecommunications and Radio Engineering
TRE
0040-2508
54
10
2000
Influence of Transversal to Geodesic Line Heterogeneity on a Field in a Waveguide Channel
2-12
10.1615/TelecomRadEng.v54.i10.10
Ludmila Nikolaevna
Lutchenko
St. Petersburg State University, Russia
Gleb Ivanovich
Makarov
St. Petersburg State University, NIIRF S.PbGU, Russia
The method of vertical modes and horizontal rays for solving the problem of a field in an irregular anisotropic waveguide is used. Complex paths of rays are constructed, and refractive effects are estimated, taking into account the dependence of the eigenvalue on azimuth at the frequency of 10.2 kHz for distances of 1.5 Mm to 9 Mm on the paths lying along the terminator. The transverse scale size for a zone in the vicinity of the path determining the field is estimated.
Weak Radiation Condition in the Diffraction of a Plane Wave by a Wedge
13-23
10.1615/TelecomRadEng.v54.i10.20
Aleksei Dmitrievich
Avdeev
Physical Faculty of St. Petersburg State University, Russia
A new method for solving the problem of plane wave diffraction by a wedge based on a modified Kontorovich-Lebedev transformation and a weak radiation condition is proposed. A solution to the problem of plane wave diffraction by a perfectly conducting wedge is constructed. The similar problem for an impedance wedge is reduced to a differential equation, the solution to which is found for the case of a wedge with right aperture angle.
Some Problems of Electromagnetic-Wave Scattering in a Waveguide Channel Irregular in Three Dimensions
24-36
10.1615/TelecomRadEng.v54.i10.30
Gleb Ivanovich
Makarov
St. Petersburg State University, NIIRF S.PbGU, Russia
Tamara Ivanovna
Bichutskaya
Institute of Radio Physics of the St Petersburg State University, Russia
The exact solution of the three-dimensional problem of scattering by a diffuse cylinder in a waveguide is obtained. The accuracy of several approximate methods of solution is discussed. The focusing and depolarizating effects of the scattered field and its dependence on the azimuth for the vertical electric dipole are investigated. The effect of ionospheric 3d-disturbance on the electromagnetic field of a point source is studied by a ray fullwave method. Several features of its influence on one- and multimode field for an irregularity posed within the first Fresnel zone and removed from one are investigated.
Use of Underground Waveguide Propagation of Electromagnetic Waves for Monitoring Mechanical Stress in Rocks
37-42
10.1615/TelecomRadEng.v54.i10.40
Mikhail I.
Belen'kii
Educational Laboratory of the Physics Department of St.-Petersburg State University, Russia
Yurii M.
Belen'kii
Center of Informational Culture, Russia
The detection method of mechanical tension in rocks by the phase measuring of electromagnetic wave in the underground guide between two boreholes is described. The amplitude and phase were calculated for a number of frequencies of sounding signal for the natural geological conditions. The result of calculations shows that the phase measurements give a possibility to detect a mechanical tension long before the destruction.
Excitation of the Earth-Ionosphere Waveguide by VLF Radiators Situated in the Lower Ionosphere and at Satellite Heights
43-68
10.1615/TelecomRadEng.v54.i10.50
Svetlana Timofeevna
Rybachek
Structural peculiarities of the electromagnetic fields excited in the Earth-ionosphere waveguide by VLF antennas situated in the lower ionosphere and at satellite heights are discussed. A model of a spherical anisotropic waveguide anisotropic in two dimensions is used. The antennas are simulated by arbitrarily oriented magnetic dipoles. The problem is solved by the cross-section method extended to the case of a two-dimensional irregularity. Within the limits of applicability of the quasi-longitudinal approximation, simple relationships between the electric and magnetic components of the fields formed by different dipoles are obtained. In the framework of a model taking into account the geomagnetic and geographic coordinates, the sun zenith angle, the azimuth, the Earth's surface properties etc., results illustrating the influence of different irregularities on the VLF field structure are obtained.
Scattering of Electromagnetic Waves by Continuous and Grid Screens in Moving Media
69-84
10.1615/TelecomRadEng.v54.i10.60
Andrei V.
Tyukhtin
Institute of Radiophysics of St-PetersburgState University, Russia
Problems of interaction of electromagnetic waves with plane screens situated in moving nondispersive medium and in moving cold plasma are considered. It is assumed that the medium is able to move both along the screen and through it (in this case, the screen was assumed to be permeable to particles of the medium). The main attention is focused on a scattering of point sources' fields by a conductive plane and on the diffraction of plane waves by the half-plane and by a slot. The basic physical effects differing radically from the effects that occur in a stationary medium are described. In additional, the averaged boundary conditions for periodic structures of parallel conductors in the above-mentioned moving media and some stationary media are given as well.
The Influence of a Curvilinear Interface on the Excitation of Electromagnetic Waves by Low-Frequency Antennas
85-93
10.1615/TelecomRadEng.v54.i10.70
Vladimir Vyacheslavovich
Zhevelev
Radio Physics Research Institute of the St. Petersburg State University, Russia
Ottiliya Georgievna
Kozina
Laboratory of the Radio Physics Research Institute of the St Petersburg State University, Russia
Gleb Ivanovich
Makarov
St. Petersburg State University, NIIRF S.PbGU, Russia
The influence of the curvature from interfaces on the efficiency of low-frequency antennas is studied. Along with determining the external current, the rigorous antenna problem is solved. It is shown that, if the antenna is situated parallel with the element of a conducting cylinder, the electromagnetic field can be doubled as compared with the case when the antenna is situated on a plane interface.
Analysis of Excitation Parameters of Low-Frequency Antennas in Conducting Media
94-100
10.1615/TelecomRadEng.v54.i10.80
Vladimir Vyacheslavovich
Zhevelev
Radio Physics Research Institute of the St. Petersburg State University, Russia
Gleb Ivanovich
Makarov
St. Petersburg State University, NIIRF S.PbGU, Russia
Excitation of low-frequency antennas in conducting media is studied. The limits in which the long-line approximation is applicable to calculating the current distribution in low-frequency antennas are determined. A possibility to increase the effective dipole moment by creating an enhanced conductivity region around the ground connection is considered.
The Large Millimeter Wave Radar Phased Antenna Array
101-111
10.1615/TelecomRadEng.v54.i10.90
Aleksey Alekseevich
Tolkachev
Joint-Stock company "Radiofizika"
Vasiliy Andreevich
Makota
Scientific research institute of radio-instrument making
Mariya Petrovna
Pavlova
Scientific and research institute of radio-instrument making
Anatoliy Moiseevich
Nikolaev
Scientific and research institute of radio-instrument making
Vladimir Victorovich
Denisenko
Joint-Stock company "Radiofizika"
Grigoriy Konstantinovich
Solov'ev
Joint-Stock company "Radiofizika"
The paper describes, apparently, the world's largest millimeter waves (MMW) antenna with a phased array. The beam steering is combined: electronic in the narrow angular range and mechanical in the wide angular range. The technical performances of the antenna and their components are given. The operating features are presented.
Research of Characteristics of a Phased Antenna Array Element in a Waveguide Simulator
112-118
10.1615/TelecomRadEng.v54.i10.100
Yurii Petrovich
Vinichenko
Anatoliy Nikolaevich
Sekistov
Alla Efimovna
Tumanskaya
The features of application of a single-element waveguide simulator for investigating the waveguide-rod element characteristics of a phased antenna array (PAA) with the circular polarized electromagnetic field for an arrangement of radiators in nodes of a triangular array are considered.
Investigation and Optimization of the Characteristics of Periodic Structures on the Basis of Two-polarized Complex Cross-section Waveguides
119-125
10.1615/TelecomRadEng.v54.i10.110
Yu. N.
Vasilenko
A. S.
Il'insky
Yu. A.
Kharlanov
The numerical investigation and optimization results of the characteristics of periodic structures on the basis of the cruciform and four-ridged (square and round) waveguides with the minimum center-to-center spacing between elements are presented. A mathematical model of an infinite antenna array consisting of arbitrary cross-section waveguides designed by the projectiion method of joining fields is used for calculations. The reflection and transmission coefficient modules, partial pattern, and elllpticity depending on the waveguide cross-section parameters are studied.