A. I. Semenikhin1, D. V. Semenikhina2, A. M. Zikina3
1–3 Institute of Radioengineering Systems and Control, Southern Federal University (Taganrog, Russia)

1 anilsem@mail.ru, 2 d_semenikhina@mail.ru, 3 a.zikina@yandex.ru

Various mechanisms of phase broadband reduction of electromagnetic wave scattering from flat shiny areas of metal bodies using non-absorbing coded metasurfaces (MS) are known: interference cancellation (destructive interference), twist-effect (polarization conversion), anomalous and diffuse scattering, spin-orbit conversion with generation of vortex waves with a spiral phase front and field zeroing on the vortex axis. In this case, Pancharatnam-Berry (PB) metasurfaces with complicated phase profiles (modified parabolic, combined, etc.) are used to improve the broadband, wide-angle, and scattering cancellation efficiency. In particular, it is known that parabolic (concave/convex) phased array metasurfaces have good scattering diffusion and are used to reduce bistatic scattering. However, Pancharatnam-Berry metasurfaces are usually designed based on unit cells of traditional square shape. The effect of the hexagonal (honeycomb) cell shape on the efficiency of phase cancellation of mono- and bistatic scattering patterns has been little studied, although in a number of other applications, metasurfaces based on hexagonal cells demonstrate better properties.

In this paper, in order to improve the phase cancellation of the scattering field, an assessment has been made of the influence of the hexagonal shape of unit cells (compared to the traditional square shape) on the damping of backscattering and the wide-angle nature of bistatic scattering from metasurfaces with convex and concave parabolic profiles of the PB-phase.

A unit hexagonal cell of the PB-metasurface with a metaparticle in the form of a perforated patch has been proposed, which effectively reflects a circular polarized wave (CP-wave) on the co-polarization with losses less than 0.35 dB and cancels a cross-polarized wave by more than 12 dB in the range from 8.5 to 19.7 GHz. MS modules from hexagonal and traditional square cells (for comparison) with the same type of metaparticles and identical parabolic convex and concave phase profiles have been designed. The MS modules have been designed from hexagonal and traditional square cells (for comparison) with the same type of metaparticles and identical parabolic convex and concave phase profiles. The scattering characteristics of co-polarized and cross-polarized CP waves have been calculated using HFSS by the finite element method in the case of normal incidence. Simulation showed that the honeycomb module reduces backscattering in the range from 8.6 to 20.7 GHz by 9.5–10 dB, while the module with square cells only by 8 dB. The metasurface with hexagonal cells provides wider-angle scattering with spread side lobes in the sector of angles of 75° (at the center frequency of 14 GHz) compared to the MS from square cells. The obtained results can be useful in choosing the shape of single cells of non-absorbing metasurfaces intended for broadband wide-angle phase scattering cancellation.

Semenikhin A.I., Semenikhina D.V., Zikina A.M. Pancharatnam-Berry metasurfaces with hexagonal cells and parabolic phase profiles for wide-angle scattering reduction. Antennas. 2025. № 6. P. 48–56. DOI: https://doi.org/10.18127/j03209601-202506-06 (in Russian)

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