Abstract：To describe the propagation characteristics of the electromagnetic wave accurately,the theory of Fresnel propagation and geometry are adopted to derive the calculation formulas of the boundary points of the electromagnetic wave propagation in the different position of the receiving and sending antenna. The simulation is taken in general arched tunnels,and the best position of the antenna is obtained which is the most conducive to the propagation of electromagnetic waves.

Keyword：arched tunnels;propagation of electromagnetic wave;near-region;division point;