This paper proposes a new propagation model to accurately predict path building-penetration loss. Account is taken of the structural openings along the paths : it is assumed that outdoor-to-indoor paths go only through the openings. Introducing angle dependency of the losses with the paths penetrating into the indoor area makes it possible to accurately predict path building-penetration loss. A series of field test took place to evaluate values of parameters related with the path building penetration such as coefficients representing angle and distance dependences of the losses. Results of the field measurements show that the proposed model can predict the path building-penetration loss more accurately than the COST231 model.
