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Snow is the most common type of solid precipitation; therefore considerable interest is the development of remote sensing methods for studying the characteristics of snow by solving the inverse problems which based on a detailed study of such precipitation properties. The radar cross sections (RCS) of few snow types in resonant wave band are demonstrated and discussed.
In this paper different and efficient acceleration techniques for the evaluation of two-dimensional Green's functions with 1D and 2D periodicities are discussed. The proposed summation numerical methods are based on the appropiate extraction of different asymptotic terms in the spectral domain representation of the corresponding Green's functions. The paper provides insight into the different formulation...
In this paper, in contrary to a common belief that Beam Propagation Method, BPM, is just a mathematical formalism not so much linked to physical phenomena, we intend to show that there is a lot of physical aspects involved. We present several examples that include also the study of radiation field (as extracted from the total beam) propagation along the optical waveguide structures that BPM allows...
A full wave analytical solution of the problem of EM plane wave diffraction by multilayered metal-dielectric sphere is presented. The proposed solution is based on variable separation method. The high numerical efficiency of the algorithm is achieved due to suggested original recurrence relations for evaluation of the fields within the multilayered sphere. The comparison of the analytical results...
The rigorous solution of the problem of axially-symmetric TM-wave diffraction by the open end of the bi-cone, which consists of finite and semi-infinite shoulders, is obtained. The structure is irradiated by the ring source of the magnetic current. The mode matching method and regularization technique are applied to obtain the problem solution. The transition from the bi-conical scatterer to the disc-cone...
Dispersion properties of both bulk and surface polaritons at the interface between vacuum and ferrite-semiconductor superlattice are studied. The superlattice is considered to be influenced by an external static magnetic field in the Voigt geometry. In order to derive tensors of effective relative permeability and effective relative permittivity of the structure under study the homogenization procedure...
An arbitrary shape called botanic curve is used for waveguide cross section which is singly connected and has enough smooth form. The boundary value problem is solved with evolutionary equations of electromagnetic theory in time domain. The real valued solutions of fields are subsequently obtained in Hilbert space. The field components depend on transverse coordinates and amplitudes are function of...
The E- polarized wave diffraction by an infinite periodic strip grating without single strip is considered. The total field is found as a sum of field of infinite periodical grating and field induced by the removal of a single strip. The problem is reduced to the singular integral equations with additional conditions. The directional patters and field distribution in the domain above the grating are...
The article demonstrates that the conditions of LF-MF-HF radio wave propagation over the “ice-sea” structure with highly inductive impedance are more favorable than over the sea without ice because of the appearance of surface electromagnetic waves (SEW). It was determined that the conditions of radio wave propagation over ice paths depend on a frequency, ice thickness and distance from the transmitter...
The specific cases of the differential Maxwell equations in the Cartesian coordinate system are considered as the basic mathematical models of electromagnetic wave propagation in the finite spatial and flat guided structures. The general wave equations uniting all scalar components of electromagnetic field vector intensities are got uniformly and are solved irrespectively to the boundary and initial...
Predictive map of geoelectric sections of the North Eurasia, necessary for calculation of propagation of VLF-MF radio waves, is constructed. Taking into account the layered structure of the underlying medium, this map is capable of increasing the accuracy of electromagnetic field calculations by 1.5–3 times as compared to the Morgan-Maxwell map and ITU-R Recommendation P.832-2. The methodology of...
The scattering problem from the curvilinear surfaces is introduced by the method of Modified Theory of Physical Optics (MTPO). The method is based on the physical optics (PO) current, on the scaterers' and aperture surfaces. The integral equation is achieved by these currents and the result is found with the stationary phase method and edge-point technique. MTPO can be applied to calculate not only...
The excitation of the guided modes of a lossless slab by a complex source point (CSP) beam is semi-analytically investigated. The goal is to compute the guided-mode powers and efficiencies as a function of problem's parameters, namely the electrical thickness, the angle of incidence, the beam aperture, and the aperture location.
The scattering of the H-polarized plane wave by a two-dimensional (2-D) parabolic reflector made of graphene placed in the free space is simulated by using the Method of Analytical Regularization (MAR) technique. The total scattering cross-section and absorption cross-section are computed, together with the field magnitude in the geometrical focus of reflector. The surface plasmon resonances are observed...
Efficiency of cross-section expansions based on the fields of waveguide with ideal walls as basis functions is investigated for impedance waveguides. The criterion of the uniform convergence with respect to the number of expansion terms is obtained. In addition, method of convergence improvement is suggested and illustrated by practical calculations.
Periodic wire grating in free space has very high-Q resonances at the frequencies close to the Rayleigh anomalies. We discuss a further enhancement of that effect by sandwiching the grating between two distributed Bragg reflectors (DBRs).
The small-sized radiators (receivers) of electromagnetic waves on the base of the system of six equidistant radial monopoles in the equatorial plane of the conducting sphere are considered. It is shown that for the antenna the various directional patterns by switching phases of voltage sources only for two monopoles can be realized. The considered radiators can be used as a small-sized sensors and...
The original fractional $-shape spiral antenna being fed from the Ka-band metal waveguide is proposed. The impedance bandwidth of such an antenna is 6.7GHz. Herewith, the axial ration does not exceed 3dB level within the limits of 34.2 – 37 GHz. The radiation pattern of such an antenna is similar to the monopole antenna with zero-radiation intensity in the antenna axis and with an elevation angle...
Conference proceedings front matter may contain various advertisements, welcome messages, committee or program information, and other miscellaneous conference information. This may in some cases also include the cover art, table of contents, copyright statements, title-page or half title-pages, blank pages, venue maps or other general information relating to the conference that was part of the original...
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