Ya.I. Chizhevskaya1, S.P. Skobelev2

1,2 PJSC Radiofizika (Moscow, Russia)

1,2 Moscow Institute of Physics and Technology (National Research University) (Dolgoprudny, Russia)

The paper describes a numerical algorithm based on the hybrid projection method for analysis of planar absorbing doubly periodic structures with spherical elements of black hole type arranged on a substrate of finite thickness with a PEC screen. The feature of the algorithm in comparison with the previous works where purely dielectric material was used for spherical elements and substrate is that it takes into account the fact that the elements and substrate are characterized both dielectric permittivity and magnetic permeability. The paper also contains derivation of new expressions for the power absorbed in the elements and substrate used for the subsequent calculation of the absorption efficiency and verification of fulfillment of the power balance relation.

The algorithm has been realized in a MATLAB code whose operation has been validated by means of studying convergence of the results with increasing the number of the retained Floquet modes and the number of the triangle functions used in the realization of the one-dimensional method of finite elements, as well as by means of controlling the accuracy of fulfillment of the power balance relation.

The paper contains a number of new results obtained with use of the code indicated above for the absorption efficiency of the structures with spherical elements. The results show that the magneto-dielectric elements can provide higher absorption efficiency in comparison with the case of using purely dielectric elements.

The results obtained for the absorption efficiency and reflection coefficients of the structures with spherical elements have been compared to the similar characteristics obtained for the structures involving pyramidal elements which are usually used in the design of anechoic chambers. The comparison shows that the structures with spherical elements allow providing performances compatible with the performances of the conventional structures with pyramidal elements but with considerably smaller thickness of the layer containing the absorbing elements.

Chizhevskaya Ya.I., Skobelev S.P. Analysis of planar absorbing periodic structures formed by spherical magneto-dielectric black holes. Radiotekhnika. 2023. V. 87. № 3. P. 40−55. DOI: https://doi.org/10.18127/j00338486-202303-04 (In Russian)

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