Indoor wave propagation modeling at low-VHF band

In this paper the feasibility and advantages of HF-VHF band for short-range and near-ground ad hoc communication in complex environment is investigated. The propagation environment is modelled by dielectric layers of vertical dielectric walls and horizontal ceilings, as well as metallic frames around the buildings. For such scenarios, a low frequency approximation known as the Generalized Rayleigh-Gans (GRG) approximation is proposed for the calculation of scattered fields by the dielectric walls. To model scattering from metallic frames the method of mathematical modal expansion for connect loops of metallic frames in conjunction with a macro-modeling approach is used to estimate the induced currents for elementary sources such as short dipoles or plane waves. The macro-model captures the variations of the modal coefficients as a function of geometrical parameters and the incident wave attributes.