**Abstract.** The paper is devoted to
simulation of the electromagnetic interaction with the forest environment. The
modeling results of radiowave scattering by the finite length obstacles are
represented. The objects of two shapes have been examined. The first of them
was composed from homogeneous coaxial cylinders. The other obstacle was the
truncated cone. There models can be used for simulation of the vegetation
components. The numerical results have been obtained on the basis of the method of discrete
sources for microwave frequencies. The scatterer parameters corresponded to
complex permittivity of trees at this band. The angular dependencies of the
scattered field have been studied. The effects of angle of incidence, different
ratios of the geometric dimensions of the obstacles and wavelength have been
carried out. The modeling results have been considered both for the case when
the cylinder length was larger of wavelength and for the case when the cylinder
length was smaller of wavelength. It has been found that the behavior of the
angular dependencies for the composite cylinder have been observed more
complicate pattern. This is due to edge cylinders diffraction. Therefore, the
simulation of the components of the forest environment by only homogeneous
coaxial cylinders can lead to significant errors.

The
numerical calculations have been carried out by TITAN X GPU supported by NVIDIA Corporation.

**Key words:** radiowave scattering, homogeneous coaxial cylinders, truncated cone, vegetation, method of discrete sources.

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