Propagation Of Electromagnetic Waves In Waveguides Research Articles

Analysis of the non-reflecting boundary condition for the time-harmonic electromagnetic wave propagation in waveguides

In this paper, we study the non-reflecting boundary condition for the time-harmonic Maxwell's equations in homogeneous waveguides with an inhomogeneous inclusion. We analyze a series representation of solutions to the Maxwell's equations satisfying the radiating condition at infinity, from which we develop the so-called electric-to-magnetic operator for the non-reflecting boundary condition. Infinite waveguides are truncated to a finite domain with a fictitious boundary on which the non-reflecting boundary condition based on the electric-to-magnetic operator is imposed. As the main goal, the well-posedness of the reduced problem will be proved. This study is important to develop numerical techniques of accurate absorbing boundary conditions for electromagnetic wave propagation in waveguides.

Change elastic felds of single crystals depending on the structure core breach

The paper is related to the issues of spent nuclear fuel (SNF) storage and radioactive waste (RW) disposal. One of the aspects of changing the structure of materials when exposed to the charged-particle beam was theoretically considered. This situation is realized in the walls of SNF storage facilities and rocks, surrounding the RW storage facilities. To solve the problem of describing the geometry of the breach core, distortions around it, integral equations of elastic waves were applied. The equations, similar to the proposed are widely used in the electrodynamics when solving the problems of electromagnetic wave propagation in waveguides and their scattering on inhomogeneities. The problem was solved by numerical methods. It was assumed that the defect had the ellipsoidal shape. The displacement fields around the core of breach cluster depending on the size of this core were found. The sizes of the core are used in the given form - the ratio of semi-axes. Single crystals of cubic structure were studied. Tungsten and gold were considered as real materials. The displacement fields on their own axes and were counted. The areas of breach core sizes, at which they are stable and steady, were defined. The side ratio, when the stress fields around the cluster of the breach core have such orientation, which leads to the compression and reduction of the central zone of the breach, was found. Further, this can cause the core collapse. Taking into account the needs of the waste storage, such breaches are preferable since they reduce the defect formation in the material, surrounding the source of ionizing radiation.

Two-dimensional electromagnetism

Starting with a discussion of the two-dimensional scalar and spinor wave equations, the author presents a formalism of the two-dimensional electromagnetism covariant under the pseudo-orthogonal group SO(2,1). He proves that this covariant formalism makes it easier and more unambiguous to discuss diffraction by plane obstacles as well as electromagnetic wave propagation in waveguides.

Electromagnetic wave propagation in waveguides with nonlinear filling

Electromagnetic wave propagation in waveguides with nonlinear filling

Propagation in Waveguides of Arbitrary Cross Section with Anisotropic Boundary

ABSTRACT The problem of electromagnetic wave propagation in waveguides of arbitrary cross section and with walls characterized by an anisotropic surface admittance is formulated in terms of an integro-differential equation for the equivalent surface currents on the walls. The solution is obtained by application of the Galerkin Moments Method technique, where triangle expansion functions are employed. This model is applied to the study of transversally corrugated waveguides. A procedure to deal with step discontinuities in the boundary conditions (e.g. partially corrugated waveguides) is presented. Comparisons with results obtained with other approaches, in the case of simple geometries, are also presented.

Guided Wave Propagation in Submillimetric Region

An analysis of electromagnetic wave propagation in waveguides (in TH and TE modes) as well as in TEM transmission lines (e.g., coaxial) at frequencies in the extremely high frequency band (30 to 300 kmc) and higher is carried out. It is shown that in the case of metallic waveguides excited in TE0 modes, the attenuation at sufficiently high frequencies is always proportional to (frequency)-3/2. On the other hand with TH waves (including TEM waves) although the attenuation at moderately high frequencies is proportional to (frequency)1/2, yet at sufficiently high frequencies the attenuation drops, becoming proportional to (frequency)-5/2. In other words, with TH waves the attenuation becomes a more rapidly decreasing funcion than it is with TE waves. The analysis is concluded with numerical examples.