RADIO PHYSICS AND RADIO ASTRONOMY

Subject and Purpose. Many of the currently known calculations of the strong absorption of electromagnetic radiation in conductors whose diameter is several hundred times smaller than the radiation wavelength proceed from the physical effects accompanying interaction of an electromagnetic wave with an infinitely long conductor. However, antenna theory shows that resonant phenomena in finite-seized conductors can significantly enhance or suppress the interaction of conductors with electromagnetic radiation. This paper examines the interaction of a thin conductor of finite length with a plane, linearly polarized electromagnetic wave, focusing in particular on the amount of energy absorption and the effects due to the length of the conductor.

Methods and Methodology. The solution to the integral equation for the current through a thin conductor has been sought for in an asymptotic averaging technique. Using the Joule-Lenz law and calculating the conductor's resistance, the power absorbed by the conductor is calculated. This allows determining the absorption efficiency factor for the radiation incident on a conductor of finite length.

Results. The amount of the electromagnetic radiation energy absorbed within a thin conductor has been studied in dependence on the conductor’s finite length. As has been found, when the length of the conductor is close to half the radiation wavelength, else to a multiple of that value, the absorption increases by tens of times compared to the value demonstrated by an infinitely long conductor.

Conclusions. The results permit clarifying the previously existing understanding of the interaction of microwave radiation with thin conducting structures and can find application in the development of compact absorbing loads, field shielding elements and structures for microwave energy transmission.

Keywords: microwave radiation, thin conductors, energy absorption, resonance effects, electromagnetic interaction

Manuscript submitted 23.06.2026

Radio phys. radio astron. 2026, 31(3): 190-198

REFERENCES

1. Zhang, D., Liao, Z., and Chen, B., 2019. Modeling of electromagnetic wave coupling to thin‐wire structures in terrain environments using hybrid PE/TPIE method. Int. J. Antennas Propag., 2019(1), 2839630. DOI: 10.1155/2019/2839630

2. Štumpfm, M., Antonini, G., and Ekman, J., 2024. Pulsed electromagnetic excitation of a thin wire — an approximate numerical model based on the Cagniard–Dehoop method of moments. IEEE Antennas and Wirel. Propag. Lett., 23(2), pp. 523—527. DOI: 10.1109/LAWP.2023.3329035

3. Dommisse, W.R., Du Plessis, J.T., Cilliers, P.I., Botha, M.M., and Rylander, T., 2024. Macro basis functions for efficient analysis of thick wires in the MoM. IEEE Trans. Antennas Propag., 72(7), pp. 5865—5876. DOI: 10.1109/TAP.2024.3400054

4. Ye, W., Liu, W., Xiang, N., Li, K., and Chen, W., 2022. Fast and accurate transient analysis of thin-wire structure in half-space with peec method. IEEE Trans. on Electromagn. Compat., 65(1), pp. 300—311. DOI: 10.1109/TEMC.2022.3215453

5. Mattucci, E., Štumpf, M., and Antonini, G., 2026.Transient plane-wave response of a dual-loaded small-loop antenna using quasi-static thin-wire partial elements. IEEE Antennas Wirel. Propag. Lett., 25(3), pp. 1279—1283. DOI: 10.1109/LAWP.2026.3653063

6. Lucido, M., Migliore, M.D., and Pinchera, D., 2016. A new analytically regularizing method for the analysis of the scattering by a hollow finite-length PEC circular cylinder. Prog. Electromagn. Res. B, 70, pp. 55—71. DOI: 10.2528/PIERB16081404

7. Schettino, F., Di Murro, F., and Lucido, M., 2025. Scattering from a finite-length closed perfect electric conducting circular cylinder: a regularized full-wave analysis. Phil. Trans. R. Soc. A, 383(2303), 20240346. DOI: 10.1098/rsta.2024.0346

8. Papakanellos, P.J., Tsitsas, N.L., and Anastassiu, H.T., 2024. The method of auxiliary sources (MAS) in computational electromagnetics: A comprehensive review of advancements over the past two decades. Electronics, 13(17), 3520. DOI: 10.3390/electronics13173520

9. Hambaryan, D., Grigoryan, N., Sarkisyan, H., and Petrosyan, S., 2024. Dielectric coated conductive rodresonantly coupled with a microwave field. Heliyon, 10(2), e24477. DOI: 10.1016/j.heliyon.2024.e24477

10. Zhang, T., Li, D., Yang, Z., Duan, Y., Zhang, N., Wang, L., and Liang, Q., 2024. A multi-materials 3D-printed continuous conductive fibre-based metamaterial for broadband microwave absorption. Virtual Phys. Prototyp., 19(1), e2285417. DOI:
10.1080/17452759.2023.2285417

11. Peymanfar, R., Dogari, H., Selseleh-Zakerin, E., Hedayatzadeh, M.H., Daneshvar, S., Amiri-Ramsheh, N., and Aslibeiki, B., 2023. Recent advances in microwave-absorbing materials fabricated using organic conductive polymers. Front. Mater., 10,
1133287. DOI: 10.3389/fmats.2023.1133287

12. Ch`en, G., Li, Z., Zhang, L., Chang, Q., Chen, X., Fan, X., and Wu, G., 2024. Mechanisms, design, and fabrication strategies for emerging electromagnetic wave-absorbing materials. Cell Rep. Phys. Sci., 5(9), 102097. DOI: 10.1016/j.xcrp.2024.102097

13. Kokodii, M.G., Natarova, А.O., Gurina, D.V., Priz, I.O., Maslov, V.O., andKarlov, V.D., 2024. Effect of anomalously strong absorption of electromagnetic radiation in fine conductive fi bers. Radio Phys. Radio Astron., 29(1), pp. 76—82. DOI: 10.15407/rpra29.01.076

14. Ufimtsev, P.Ya., 2010.Theory of Edge Diffraction in Electromagnetics. Encino, CA, USA: Tech Science Press.

15. Nesterenko, M.V., Katrich, V.A., Penkin, Yu.M., Dakhov, V.M., and Berdnik, S.L., 2011. Thin Impedance Vibrators: Theory and Applications. Springer Science+Business Media, New York, 460 p.

16. Werner, D.H., Werner, P.L., and Breakall, J.K., 1994. Some computational aspects of Pocklington’s electric field integral equation for thin wires. IEEE Trans. Antennas Propag., 42(4), pp. 561—563. DOI: 10.1109/8.286230

17. Forati, E., Mueller, A.D., Yarandi, P.G., and Hanson, G.W., 2011. A new formulation of Pocklington’s equation for thin wires using the exact kernel. IEEE Trans. Antennas Propag., 59(11), pp. 4355—4360. DOI: 10.1109/TAP.2011.2164211

18. Bogolyubov, N.N., and Mitropolsky, U.A., 1974. Asymptotic Methods in the Theory Nonlinear Oscillations. Nauka Publ., Moskow, 410 p.

19. Filatov, A.N., 1974. Asymptotic Methods in the Th eory of Differential and Integral-diff erential Equations. FAN, Tashkent, 216 p.

20. Nesterenko, M., 2010. Analytical methods in the theory of thin impedance vibrators. Prog. Electromagn. Res. B, 21, pp. 299—328. DOI: 10.2528/PIERB10020105

21. King, R., Wu, and Tai, Tzun, 1959. Scattering and Diffraction of Waves. Harvard University Press, 236 p.

22. Kokodii, M., and Gurina, D., 2025. Absorption of microwave radiation in a thin conductor of finite length. In: Proc. Xth Ukrainian Scientific-Practical Conf. on Prospective Directions of Modern Electronics, Information and Computer Systems
(MEICS), Dnipro, Ukraine, 26—28 Nov. 2025, pp. 240—241.