Comparison of 3D volume integral equation and ray tracing for indoor propagation modelling

This paper presents a comparison between a volume electric field integral equation (VEFIE) modelling approach and ray tracing for the purposes of indoor propagation modelling. Focus is drawn to the inclusion of multiple internal interactions in the computation of reflections and transmissions in ray tracing. Results are presented for lossless and lossy materials. It is found that including multiple internal reflections improves the agreement between the ray tracing model and the VEFIE for reflections from a slab whilst there is a negligible improvement when considering transmissions through the slab. It is shown that when considering reflections from a slab it is more beneficial to consider internal interactions over diffraction but for transmissions through the slab other electromagnetic phenomenon are of more benefit than internal interactions.