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We study the scattering of a vegetation canopy consisting of a large number of thin cylindrical scatterers using Numerical Maxwell Model in 3D Simulations (NMM3D). The full wave approach for solving Maxwell equations is based on the Foldy-Lax multiple scattering equations (FL) combined with the Method of Moments for bodies of revolution (BOR). The accuracy of the method FL-BOR is first validated by...
Unmanned aerial vehicles (UAVs) can generally operate under very different conditions from a radiowave propagation point of view. This also includes scenarios where the presence of vegetation can be in a close vicinity of the UAV or its ground control station. Treating the interaction of electromagnetic waves and vegetation has always been of great interest and thus, so far, different approaches have...
Vegetation effects on electromagnetic wave propagation can have a strong impact on many localization or communication systems. This situation explains an increasing interest in the development of tree attenuation and scattering models which could help in the characterization of complex propagation environments. In this paper, we propose a general methodology to compute propagation effects due to a...
In this paper, results from two studies, one for ESA, the European Space Agency, awarded to a contortion led by Joanneum Research (A), and the other for CNES, the French National Space Studies Center, awarded to ONERA (F), are presented. These studies had the task of evaluating the characteristics of both the narrowband and wideband channels at Ku- and Ka-Band so that the feasibility of setting up...
This paper presents a physical statistical model to simulate the Ku/Ka band LMS channel. It describes the effect of individual obstacles on the channel and the methodology to simulate flexible environment relying on different 3D databases. A particular emphasis is put on the singularity induced by the use of high frequency band. The validation with regards to existing data and tools is also considered.
In a vegetated residential area, a wireless system has the base-station transmitter located close to the surrounding rooftops, so that propagation takes place over the rooftops and through the canopy of the trees that are above the houses. For a receiving antenna on the street level, the propagation loss can be decomposed into three components namely free space, multi-screen diffraction and rooftop-to-street...
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