For indoor wireless communication systems, transceivers need to be placed strategically to achieve optimum communication coverage area at the lowest cost. Unfortunately the coverage region for a transceiver depends heavily on the type of building and on the placement of walls within the building. This paper proposed a slab model to simulate the wave transmission in the wall and employed this simple path loss model to predict the coverage region. This method prevents the complicated computation of wave propagation, so it could predict the coverage area real time. Numerical results show predicted path loss date are well agreed with the measurement ones.