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—The properties of axial and helical metaparticles of pulse wave fields are presented. An example of emission of such metaparticles by an aperture source is considered. The field width and the energy density of a fundamental (zero) metaparticle in the far field of the radiating aperture are calculated.

The paper considers the properties of a directionally radiated axisymmetric pulse of a wave field represented as a set of axisymmetric metaparticles of pulsed wave fields. The value of the energy transferred by the considered pulse and obtained as the sum of the energies of the constituent metaparticles is found.

The study estimates distance at which the effective transverse size of a field of metaparticle directionally radiated by an aperture source is preserved in order of magnitude during as metaparticles propagate from the aperture. Thus, the ray pattern of the radiation field of metaparticles is preserved.

—The results of analyzing changes in the transverse size of the effective shape and radius of curvature of the phase wave front of a field of metaparticles during their directed propagation from the aperture source of a pulsed wave field are presented.

Properties of elementary particles of pulsed (localized) electromagnetic and acoustic wave fields directionally radiated by aperture sources (antennas, lasers, acoustic diaphragms) in free space and homogeneous isotropic media, for which the term metaparticle is used, are considered. The structure of the wave field and the energy transferred by the metaparticles are presented. The results obtained for the presented scalar theory of metaparticles of pulsed transverse electromagnetic (TEM) waves and longitudinal elastic acoustic waves can be extended to vector pulsed wave modes guided by layered inhomogeneous guiding media and guiding technical devices (waveguides).

The properties of a surface wave directed by a plane ribbon made of a nonmagnetic material with a high surface conductivity are investigated. Using the model of an equivalent ribbon with an elliptical cross section, the complex slowing (corresponding to the real part) and attenuation (corresponding to the imaginary part) ratio is approximately calculated in the case when a wave propagates along the ribbon. Approximate estimation values for the phase, group, and energy velocities of the surface wave are also obtained.

The regularities of transition of phase and group velocities from slow surface waves (whose velocities are below the light speed) to fast surface waves (whose velocities are above the light speed) on the plane boundaries of highly conducting media are investigated when the parameters of media vary. It is shown that the structure of waves does not change qualitatively in the case of this transition: the waves remain to be surface ones in contrast to surface waves of dielectric waveguides. The latter ones are transformed into leaking waves or their structure changes in a more complicated way in the case of such transition. A result relating, in particular, to the Zenneck wave is obtained.

Effective excitation of a surface wave, in particular, the Zenneck wave, over a plane boundary of a highly conductive medium is considered.

The focusing properties of a converging spherical wave that passed the plane boundary of a medium are investigated in the ray approximation. Models of the medium of the two types are considered—ignoring and taking into account the wave energy loss in the medium. The dimensions of the localized volume spot of the field formed instead of the focusing point are estimated.

The efficiency of excitation of the surface wave, in particular, the Zenneck wave on the plane boundary of an electrically conducting medium with high conductivity by a vertical aperture is introduced and analyzed.

The process of focusing of surface electromagnetic waves on impedance guiding surfaces is considered in the ray approximation with the help of a 2D model of a plane surface. An estimate of the influence of the wave properties of the field on this process is given.

Estimation analytical expressions are obtained for the group and energy velocities of the Sommerfeld surface electromagnetic wave on a conducting cylinder with a high conductance: a metal wire model and a water stream.

The physical properties of boundary surface electromagnetic waves at interfaces of high-conductivity media substantially differ from the well-known properties of the surface waves that are guided by dielectric waveguides. The earlier conclusion that the three velocities of such waves (phase, group, and energy) are different (so that the group velocity differs from the energy velocity) is proven. It is also demonstrated that the conventionally determined group velocity does not have the commonly accepted physical meaning, since it can be greater than the velocity of light, whereas the energy velocity (the velocity at which the energy is transferred) is less than the velocity of light in free space. The Brewster effect is not observed in the field structure of the waves under study (in particular, Zenneck waves). The application of the Leontovich surface impedance in the analysis of the boundary surface waves is substantiated.

Quantitative estimates are obtained for the smallest values of the radii of curvature of longitudinal bends of the boundaries of highly conducting media and the largest transverse deviations of gradually curved (irregular) boundaries from the plane of the corresponding surface at which boundary surface waves propagate along the boundaries of such media without a substantial additional (to absorption in the medium) energy loss for radiation into space.

It is revealed in the ray approximation that focusing of a converging spherical wave traveling through the boundary of a material medium can be retained if a lens-like pad is used on the medium boundary. Conditions imposed on the parameters of such a pad are presented. Dimensions of the volumetric spot in the region of the wave focusing point are estimated with consideration for the Fraunhofer diffraction at the edge of a round pad.

The properties of fundamental (lower) guided wave modes propagating in a nonsymmetric planar metamaterial waveguide are considered. A graphical approach is applied for the analysis of their dispersion characteristics oriented toward the determination of the waveguide’s parameters ensuring the propagation of these waves in the waveguide. It is shown that, a nonsymmetric waveguide, as a symmetric one, can support both forward and backward wave modes.

The guided-wave transmission and reflection coefficients, the pattern, and the energy of the radiated field are calculated as functions of the value of the displacement at the junction of two single-mode waveguides for various values of the permittivity of waveguiding layers. It is shown that the correction to the wave transmission coefficient calculated at the first and second iteration steps increases while the permittivity grows, and the way this correction increases is demonstrated.

The distribution of the field excited by a point source in the neighborhood of the focal point of a plane metamaterial lens is numerically calculated. The presented results illustrate the previously obtained estimate of the effective dimensions of the spot, i.e., the field concentration in the neighborhood of the focal point.

Different approaches to the problem of estimation of the direction of arrival of the incident wave with an unknown polarization are considered. It is found that the obtained solutions can be used to increase the accuracy and reliability of direction finding due to elimination of polarization errors and to determine the polarization parameters as an additional information parameter. Analysis of the results obtained for a particular configuration of the antenna array is performed. It is shown that the proposed method is more efficient for determination of the direction to the source of an arbitrarily polarized electromagnetic field than the approaches oriented to processing of the field with a predetermined polarization. The results of a numerical simulation confirming these conclusions are presented.

The focusing properties of a double-layer plate (plane lens) made of isotropic chiral electromagnetic media with negative permittivity and permeability are considered.

A rigorous analytic method is used to solve the wave-propagation problem for a planar transversal junction of two planar waveguides. The problem is reduced to an iteratively solved system of integral equations of the second kind. Dependences of the transmission and reflection coefficients of guided waves, radiation patterns, and the power of the radiation field on the ratios of the waveguide thicknesses and the waveguide permittivities are obtained.

A system of two pair summatory equations and a coupling equation for LM and LE waves in a grating are obtained. The summatory equations are solved with the use of the Galerkin method with allowance for the edge singularity. Computation results are presented for multiresonance gratings containing several rings in an elementary cell.

A rigorous analytic approach to solution of the problem of wave propagation through a plane transverse junction of two open waveguides is proposed. According to the method developed, the problem is reduced to a system of integral equations of the second kind, which is solved with the help of iterations. The use of the method is exemplified by its application to the problem for a coaxial junction of two circular metal/dielectric waveguides.

The reciprocity principle and the concept of the group and energy velocities are generalized to the fields and waves in chiral media and guiding structures.

Excitation of a microstrip waveguide by means of a microstrip line and waveguide transitions between microstrip waveguides characterized by different parameters are investigated theoretically.

A microstrip waveguide with a smooth or an angular bend lying in the plane of the guiding strip is considered. Losses of the fundamental mode traveling along strip bends are analyzed theoretically for the one-and two-mode regimes.