Zhurnal Radioelektroniki - Journal of Radio Electronics. eISSN 1684-1719. 2022. №2
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Full text in Russian (pdf)

DOI: https://doi.org/10.30898/1684-1719.2022.2.12

UDC: 621.391.01

MODELS OF SIGNAL DISTORTION DURING PROPAGATION IN FOREST LANDS

L.Е. Nazarov

Fryazino branch of the Kotelnikov Institute of Radioegineering and Electronics of RAS, Vvedensky Sq. 1, Fryazino Moscow region, 141120, Russia

The paper was received February, 18 2022

Abstract. Models of signal propagation in forests are presented, based on the representation of forests as a continuous quasi-homogeneous medium and characterized by an effective complex permittivity. The values of the effective permittivity are a functional of the total volumetric concentration of the components of vegetation relative to the main medium - the atmosphere, of the frequency of signals, of the electrical and taxometric characteristics of forests. It is shown that when propagating along the lines under consideration, the spectral components of digital signals acquire partial phase and amplitude shifts, which causes distortions of the complex envelopes of signals and energy losses during reception with respect to propagation in free space. Modeling was carried out using models of signal propagation in forests with typical characteristics to estimate the probabilistic characteristics of receiving digital signals with 4-level phase shift keying with frequency band extension. It is shown that for these signals with a frequency band of 10...20 MHz with a center frequency of the P-band with horizontal polarization, the energy loss with respect to propagation in free space with equivalent attenuation exceeds 1.2 dB due to the distortion of the complex envelopes of the signals. A smaller effect on the probabilistic characteristics of receiving signals with vertical polarization is also shown - the energy loss in this case reaches 0.5 dB.

Key words: phase shift keying signals, forests, models of signal propagation, effective complex permittivity, energy loss

Financing: This study was supported by the Russian Foundation for Basic Research, project 20-07-00525

Corresponding author: Nazarov Lev Evgenievich, levnaz2018@mail.ru

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For citation:

Nazarov L.E. Models of signal distortion during propagation in forest lands. Zhurnal radioelektroniki [Journal of Radio Electronics] [online]. 2022. №2. https://doi.org/10.30898/1684-1719.2022.2.12 (In Russian)