A.S. Yashchenko 1, S.V. Krivatsevich 2

1,2 Institute of Radiophysics and Physical Electronics, Omsk Scientific Center SB RAS (Omsk, Russia)

1 x_rays@mail.ru; 2 kriser2002@mail.ru

At this moment, the underlying surface is considered as a homogeneous dielectric medium in the model's interaction of electromagnetic waves in the MF, HF, and VHF bands. However, the values of the soil's complex dielectric permittivity in natural conditions vary with depth. This paper presents the results of the estimate of the effective's values of complex dielectric constant for such an inhomogeneous medium. For this, we calculated the reflectivity from inhomogeneous soil. Further, we chose the values of the complex dielectric permittivity and conductivity of a homogeneous dielectric with similar reflective characteristics. Such values complex dielectric permittivity and conductivity are called effective. We used the data of complex dielectric permittivity for loamy clay soil obtained in laboratory condition and soil moisture data measured in situ in the surface layer of 2 meters. The samples of loamy clay soil were taken in the south of the Omsk region. This type of soil is typical for this territory. It is shown that the values of the effective dielectric permittivity are dependent on the view of the soil moisture profile in the toplayer. It was found that under certain conditions the equivalent values of the CDP of the underlying surface, found at different frequencies, could differ significantly from each other. The reason for this is the highly heterogeneous soil moisture profile in the surface layer and the difference in skin layer thicknesses for different wavelengths. The possibility of this effect manifestation must be taken into account when assessing the nature of the interaction of electromagnetic waves with the underlying surface.

Yashchenko A.S., Krivatsevich S.V. The estimation of effective values of the underlying surface dielectric permittivity. Radiotekhnika. 2020. V. 84. № 12(24). P. 121−127. DOI: 10.18127/j00338486-202012(24)-12 (In Russian).

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