S.P. Skobelev1

1 PJSC “Radiofizika” (Moscow, Russia)

1 Moscow Institute of Physics and Technology (National Research University) (Moscow, Russia)

1 s.p.skobelev@mail.ru

The communication is devoted to consideration of spherical and cylindrical end-fire antennas filled with electric and magnetic currents. Continuous distributions of the currents correspond to point Huygens elements forming a uniform plane wave running in the axial direction with specified slowing coefficient. Radiation patterns corresponding to the indicated antennas have been derived and subsequently used for calculation of the antenna directivity. Optimal values for the slowing coefficient at which maximum antenna directivity is achieved have been found. There have been carried out comparisons of the maxima directivity of a spherical antenna of specified range of radius and there modifications of a cylindrical antenna of the same volume. There have also been carried out calculations of maximum values of directivity for a circular aperture, a linear traveling wave radiator, and a cylinder of maximum volume inscribed in a sphere of specified radius. It is shown that directivity of spherical and cylindrical end-fire antennas with optimized slowing coefficient can significantly (up to 5 dB) exceed the well-known limit level 3+(ka)2 where k is the wavenumber and a is the radius of a minimal sphere enclosing the antenna.

Skobelev S.P. Maximal directivity of spherical and cylindrical end-fire antennas filled with continues distribution of Huygens elements. Radiotekhnika. 2026. V. 90. № 4. P. 68−74. DOI: https://doi.org/10.18127/j00338486-202604-09 (In Russian)

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