Accuracy improvement of ray-launching approach for indoor wave propagation through high lossy walls

This paper focuses on the transmitted wave through an indoor wall, which is composed by high lossy dielectric material. According to the Snell's law, refracted propagation (real) angle thetas
_t
may be extended to a complex angle thetascirc
_t
for such lossy dielectric case. Especially, if the lossy effect of the wall material is large, Jfrm{thetascirc
_t
} may not be negligible small. In the ray-launching procedure, the complex angle thetascirc
_t
must be replaced with real shooting angle thetas
_t
, when one needs to calculate the transmitted ray through the wall. However, it is not clear how one determines the appropriate real shooting direction thetas
_t
inside the wall when the refracted angle becomes complex. In order to clarify the above question, this paper considers how to determine the appropriate real refracted angle thetas
_t
, by comparing the numerical ray-launching solution with the analytically derived reference solution. Accuracy improvement for higher lossy material cases is also discussed. Here time harmonic factor e
^-iwt
is assumed and suppressed throughout the context