Security communication in winding tunnels and deep underground streets

Abstract

In underground environments, communicability is vital in emergency cases such as fires, as well as in routine management operations. In a disaster the lines of the wire communication system may be damaged. Therefore, a simple wireless device is necessary for the preservation of public safety. This study aims at establishing a basis for solving such problems. In this paper, we have analyzed the propagation characteristics of the Crank-Tunnel. To solve such a boundary value problem, we have introduced the boundary-element method and the surface impedance approximation. In addition, reflector placed at the corner improves the radio communication characteristics in crooked tunnels.<>