Journal of Radio Electronics. eISSN 1684-1719. 2025. ¹3

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DOI: https://doi.org/10.30898/1684-1719.2025.3.11

 

 

 

TROPOSpHERIC REFRACTION SENSING

USING THE AUTOMATIC DIFFERENTIATION

OF THE PARABOLIC EQUATION

 

M.S. Lytaev

 

St. Petersburg Federal Research Center of the Russian Academy of Sciences,

199178, Russia, Saint Petersburg, 14 Linia, 39

 

The paper was received December 6, 2024.

 

Abstract. A method for indirect measuring the vertical profile of the tropospheric refractive index is proposed. The method is based on analyzing the distortion of a radio signal as it propagates near the Earth's surface from a known source to an array of receivers. The parabolic equation method is chosen as the direct model. Automatic differentiation with respect to the unknown parameters of the target profile is applied to the finite-difference numerical scheme. This approach enables efficient computation of the gradient required for solving the optimization problem. Computational experiments conducted for various profiles and frequencies demonstrate the adequacy and effectiveness of the proposed method.

Key words: inverse problem, tropospheric refractive index, parabolic equation, tropospheric waveguide.

Financing: This study was supported by the Russian Science Foundation grant ¹23-71-00069.

Corresponding author: Lytaev Mikhail Sergeevich, mlytaev@yandex.ru

 

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For citation:

Lytaev M.S. Tropospheric refraction sensing using the automatic differentiation of the parabolic equation // Journal of Radio Electronics. – 2025. – ¹. 3. https://doi.org/10.30898/1684-1719.2025.3.11 (In Russian)