The Excess Attenuation of Electric Field in the Presence of Deciduous Trees

Abstract

Excess attenuation of electric field of an electromagnetic wave propagating through deciduous forest is approximated with two novel analytical formulas. The coefficients of those formulas were obtained through a computationally intensive optimization process by fitting the simulation results obtained from stochastic 3D and 2D models of forests. The electric field was either vertically or horizontally polarized, at frequencies 30 MHz, 60 MHz and 100 MHz. According to numerical experiments, these formulas predicted the excess attenuation within several decibels, up to at least 100 MHz. Nevertheless, the proposed formulas matched very well the measured data from literature below 1 GHz, and neatly followed the measurements even up to 10 GHz. Therefore, the frequency range considered in the numerical experiments can be extrapolated at least tenfold.

Keywords

• Attenuation
• approximation formula
• electromagnetic waves
• modeling
• full‑wave electromagnetic simulation
• trees