Research on application of wireless communication technology in cable tunnels

The paper first gives a general review about the studies on the wireless communication of the cable tunnels, then analyzes the technical requirements of signal coverage in the electric power tunnel, and finally puts forward a new way of wireless intercom communication in the tunnel. In this way, several transmitters in the electric power tunnels simultaneously send the same signal over the same frequency channel and the signal covers both the area on the ground and in the tunnel. The way means forming a network with the wireless simulcasting control technology above the ground, using multiple wireless link simulcasting base stations to finish a wide range of simulcasting coverage, setting up a lot of broadcasting receiving/transmitting stations in the tunnel, arranging the directional antennas and the transfer amplifiers in the cable tunnel according to the tunnel´s length, width, branching, etc, and thus achieving multi-directional uniform coverage with the same frequency in the tunnel. Forming a network between the surface and the underground, and then achieving connection between the users in the tunnel and on the ground, and communication scheduling by the dispatch center to the users.