Abstract
Electromagnetic (EM) waves propagating around buildings have been studied by measurement and numerical simulations taking into account building's structures as one of the researches concerning to finding ways to improve EM environment inside tunnels and undergrounds. In this paper, the effect of the periodic round convexities being put on concrete walls on reflection waves has been studied by the two dimensional EM wave propagation analysis using the CIP (Constrained Interpolation Profile Scheme) method. The numerical results obtained by these simulations show that the reflection waves from the wall having round convexities become higher than that from the flat wall in some cases. It means that electric field strength reflected from the wall having periodic round convexities has a frequency characteristic depending on periodic intervals of round convexities. As a practical use of round convexities, the electric field distribution inside the L shape tunnel is compared between the case that round convexities are put on a wall and the case that all walls are flat.
