An acceleration technique for Ray Tracing simulation based on a shadow volumetric binary and line space partitioning

Ray tracing (RT) techniques are widely employed to estimate the field levels both in urban areas and within building (indoor propagation). The radio propagation is modeled as a set of plane waves, approximated by rays which, undergoing multiple scattering phenomena (reflection, diffraction, transmission), link the transmitting to receiving antennas. Typically, the computational time of RT tools quickly increases as the complexity of the scenario and the maximum order of bouncing allowed grow. Several acceleration techniques have been proposed based on a reduction of the total number of ray-facet intersection tests [1-2-3]. In order to reduce the allowed rays, one can resort to algorithms typically employed in computer graphics: to this end, an evaluation of visibility relations between pair of facets and between facets and transmitting/receiving antennas is needed (two objects - antenna or facets - are visible if and only if a not occluded direct ray can be traced between them).