Solar-Terrestrial Physics Solar-Terrestrial Physics Solar-Terrestrial Physics 2500-0535 58060 10.12737/stp-94202311 Results of current research Results of current research Results of current research HF radio channel modeling by a waveguide approach HF radio channel modeling by a waveguide approach https://orcid.org/0000-0001-5120-1150 Куркин Владимир Иванович Kurkin Vladimir Ivanovich kurkin@iszf.irk.ru

доктор физико-математических наук;

doctor of physical and mathematical sciences;

 Ильин Николай Викторович Ilyin Nikolay Viktorovich ilyin@iszf.irk.ru

кандидат физико-математических наук;

candidate of physical and mathematical sciences;

 Пензин Максим Сергеевич Penzin Maksim Sergeevich penzin.maksim@gmail.com https://orcid.org/0000-0002-1371-6855 Пономарчук Сергей Николаевич Ponomarchuk Sergey Nikolaevich spon@iszf.irk.ru

кандидат физико-математических наук;

candidate of physical and mathematical sciences;

 Хахинов Виталий Викторович Khakhinov Vitaliy Viktorovich khakhin@iszf.irk.ru

кандидат физико-математических наук;

candidate of physical and mathematical sciences;

 Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar-Terrestrial Physics SB RAS Irkutsk Russian Federation Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar Terrestrial Physics SB RAS Irkutsk Russian Federation Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar Terrestrial Physics SB RAS Irkutsk Russian Federation Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar-Terrestrial Physics SB RAS Irkutsk Russian Federation Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar Terrestrial Physics SB RAS Irkutsk Russian Federation 28 12 2023 28 12 2023 9 4 83 94 30 03 2023 15 09 2023 https://zh-szf.ru/en/nauka/article/58060/view

We present a modified method of HF radio channel modeling based on a waveguide approach. The waveguide approach represents the electromagnetic field of radiation inside the Earth—ionosphere waveguide as an eigenfunction series of a radial boundary problem with impedance conditions on the Earth surface and radiation conditions at infinity. The transfer function of the radio channel is represented as a series of products of angular-operator Green functions, excitation coefficients, and coefficients for receiving individual normal modes. We have obtained a solution of the boundary value problem of determining the eigenfunctions and eigenvalues of the radial operator. The solution can be applied to the frequency range below the ionospheric F-layer critical frequency. We examine algorithms for calculating distance-frequency, frequency-angular, and amplitude characteristics of signals by analyzing and numerically summarizing the series in terms of strongly damped normal modes.

We present a modified method of HF radio channel modeling based on a waveguide approach. The waveguide approach represents the electromagnetic field of radiation inside the Earth—ionosphere waveguide as an eigenfunction series of a radial boundary problem with impedance conditions on the Earth surface and radiation conditions at infinity. The transfer function of the radio channel is represented as a series of products of angular-operator Green functions, excitation coefficients, and coefficients for receiving individual normal modes. We have obtained a solution of the boundary value problem of determining the eigenfunctions and eigenvalues of the radial operator. The solution can be applied to the frequency range below the ionospheric F-layer critical frequency. We examine algorithms for calculating distance-frequency, frequency-angular, and amplitude characteristics of signals by analyzing and numerically summarizing the series in terms of strongly damped normal modes.

 radio wave propagation radio channel waveguide approach simulation ionosphere sounding radio wave propagation radio channel waveguide approach simulation ionosphere sounding The work was financially supported by the Ministry of Science and Higher Education of the Russian Federation (Subsidy No. 075-GZ/Ts3569/278) The work was financially supported by the Ministry of Science and Higher Education of the Russian Federation (Subsidy No. 075-GZ/Ts3569/278)

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