Journal of Radio Electronics. eISSN 1684-1719. 2026. ¹8

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DOI: https://doi.org/10.30898/1684-1719.2026.8.12

 

 

 

TRANSMISSION COEFFICIENT BETWEEN ANTENNAS
AS A SOLUTION OF THE SCALAR HELMHOLTZ EQUATION

 

N.V. Anyutin1,2

 

1Public joint-stock company “Research and Production Corporation “Almaz”,
125190, Russia, Moscow, Leningrad Avenue, 80, b. 16

2Moscow Institute of Physics and Technology,
141700, Russia, Dolgoprudny, Institutskiy pereulok, 9

 

The paper was received October 21, 2025.

 

Abstract. The article demonstrates that for antennas translations, the transmission coefficient between them satisfies the scalar Helmholtz equation. A new transmission formula is derived. It differs from the Kerns transmission formula in its integration limits and the presence of a weight function. The weight function selects a unique linear combination of two scalar plane waves propagating towards each other. This allows calculating the transmission coefficient for any relative antenna position, except when their volumes intersect.

Key words: radiation pattern, transmission formula, transmission coefficient, mutual coupling, antenna measurements.

Corresponding author: Anyutin Nikolay Viktorovich, anyutinnv@mail.ru

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For citation:

Anyutin N.V. Transmission coefficient between antennas as a solution of the scalar helmholtz equation. // Journal of Radio Electronics. – 2026. – ¹. 8. https://doi.org/10.30898/1684-1719.2026.8.12 (In Russian)