Traveling the weak field and the same frequency; in the transfer operation, there is often a large operation site, or the Tunneling of the Railway Station of Chengshan District is mixed with tunnels, roads, etc., and the wireless communication covers the weak field, causing communication. Impact production safety and efficiency.  
The repeater can utilize the same frequency to realize the truck voice, signaling, and the transfer operation plan long-distance relay transmission, effectively solve the coverage of the mobile phone wireless communication weak field, improve the efficiency of work, and reduce the probability of safety incident.