Diffraction Radiation Phenomena: Physical Analysis and Applications

Diffraction Radiation Generated by a Density-Modulated Electron Beam Flying Over the Periodic Boundary of the Medium Section. Iii. Anomalous and Resonant Phenomena

“…The foundations were established for a reasonably rigorous mathematical modeling of diffraction radiation processes, which, in turn, made it possible to significantly expand the scope of the phenomena under the study due to the inclusion in them the so-called 'wave analogs of SPR and VChR' -the role of the intrinsic field of a beam of charged particles is played here by the field of an inhomogeneous plane wave or of a field of a surface wave directed by an open, for example, dielectric waveguide, and the polarization of this field can be arbitrary. New tasks, new results, and new opportunities for their practical use have appeared (see, for example, works [10,[16][17][18][19][20][21][22]).…”

Diffraction Radiation Generated by a Density-Modulated Electron Beam Flying Over the Periodic Boundary of the Medium Section. I. Analytical Basis

“…Classical works [3][4][5][6] are devoted to the theory of these phenomena and their practical use. The surge of interest to them in modern science (see, for example, [7][8][9][10][11][12][13][14][15][16][17][18]) is mainly due to: (a) a significant progress of computational physics, which allows to formulate and solve rather complex problems that are adequate to the situations under study; (b) the invention and fabrication of new artificial materials and media with unique properties not previously considered; (c) a growing list of relevant physical and applied problems, whose solution is facilitated or could be facilitated by new knowledge about the processes of diffraction radiation (VChR or SPR).…”

Axial-Symmetric Diffraction Radiation Antenna with a Very Narrow Funnel-Shaped Directional Diagram

“…In diffraction radiation antennas (or simply in diffraction antennas) [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24], wave analogs of SPR and VChR are implemented. It is impossible to say that they were very widespread, but several dozen devices of this type, unique in their characteristics, have been constructed at O.Ya.…”

“…In operating systems, mainly linear [7,9,12,16,[18][19][20][21][22] and planar [7,10,11,[13][14][15][16][17]24] antennas of diffraction radiation were used. In the radiator of a linear antenna, the grating width and the effective width of the open (dielectric) waveguide are from half to two wavelengths, and the length of the radiating aperture is from several tens to several hundred wavelengths.…”

“…Axially symmetric emitters based on circular dielectric waveguides and Goubau lines have been studied well enough theoretically [17,22,25], but they were implemented only in laboratory models and in prototypes with short apertures-they were used to solve the problems of synthesizing antennas with full-size apertures. The axially symmetric structure considered in this work implements a wave analogue of Smith-Purcell radiation in the 'radial dielectric waveguide-concentric periodic grating' system and is capable, due to the specific geometry of such a system, to form a radiation field with a very narrow funnel-shaped directivity pattern near the throat.…”