Journal of Radio Electronics. eISSN 1684-1719. 2026. ¹4
Full text in Russian (pdf)
DOI: https://doi.org/10.30898/1684-1719.2026.4.10
ON THE CALCULATION OF THE FIELD STRENGTH
IN THE FAR ZONE OF AN ELEMENTARY LOOP ANTENNA
LOCATED IN THE EARTH'S IONOSPHERE
A.V. Moshkov
Kotelnikov IRE RAS
125009, Russia, Moscow, Mokhovaya str., 11, b.7
The paper was received April 2, 2026.
Abstract. A low-frequency loop antenna located in the ionosphere can be used as an effective tool for plasma diagnostics and radio communications. The problem of finding the far field of an antenna in a magnetoplasma such as the ionosphere was solved by several workers earlier. It was shown that the results may be reformulated in a simpler manner to express them in terms of the normalized characteristic plane waves of the medium. This has the advantage of showing clearly how the far field depends on the free space pattern of the antenna, on the shape of the dispersion surface, namely, on the curvature characteristics of this surface. This paper presents a relatively simple and intuitive computational procedure for determining the far-field strength of any small-sized (compared to the wavelength) source located in a cold, homogeneous, multicomponent magnetoactive plasma (the ionosphere), provided that the source's radiated power and its power radiation pattern are known. As an illustration, the results of calculating the field strength in the far zone of an elementary loop antenna located in the ionosphere are given for frequencies of 1 and 100 kHz. A qualitative analysis of the angular and frequency distribution of the field strength is performed for parallel and perpendicular orientations of the loop antenna. It is shown that plasma resonance and multipath propagation, arising from plasma anisotropy, lead to a significant angular redistribution of the loop field strength compared to radiation in free space.
Key words: ionosphere, loop antenna, radiation pattern, far fields of the loop.
Financing: the work was carried out on the topic of the state assignment of the Kotelnikov IRE RAS No. FFWZ-2022-0014.
Corresponding author: Moshkov Aleksandr Vladimirovich, kuzaf@inbox.ru
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For citation:
Moshkov A.V. On the calculation of the field strength in the far zone of an elementary loop antenna located in the Earth's ionosphere // Journal of Radio Electronics. – 2026. – ¹. 4. – 2026. – ¹ 4. https://doi.org/10.30898/1684-1719.2026.4.10 (In Russian)