A SBR estimation for indoor wave propagation through dielectric walls

For indoor multihop- or relaying-based wireless systems, it it is important to comprehend the complex propagation mechanisms, and, hence, a high speed propagation estimation method is required. Indoor electromagnetic wave propagation through dielectric walls is analyzed using a ray tracing method, which is based on a high frequency ray launching or SBR (shooting and bouncing ray) technique. In the previous SBR analysis for indoor environment with many walls (Sato, R. et al., 2005), three fundamental GO components, direct, reflected and transmitted rays, have been considered. However, the contribution of multiple reflections inside the walls has not been included in the study. To derive the multiple reflections representation analytically, the Green´s function problem for a line source in the presence of a dielectric slab is considered, and the asymptotic Green´s function representation for each ray is obtained using the collective ray approximation. Taking into account the derived complementary terms for the multiple reflections inside the slab, an accurate numerical result for a simple indoor model is obtained. In comparison with the FDTD result, the validity of the present SBR solution with multiple reflections is confirmed.