Abstract: With the widespread marketing of 5G applications, major telecom providers have already been experiencing varied degrees of frequency scarcity. The preferred plan of Telecom operators is to shut down 2G and 3G networks and reallocate the spectrum to 4G and 5G networks. The 850, 900, 1,800, 1,900, and 2,100 MHz frequency bands are used by 2G and 3G networks. The Sub-1 GHz frequency band is particularly advantageous for indoor coverage and penetration. The elimination of 850 and 900 MHz transmissions has been prioritized by operators. However, a sizable portion of power acquisition terminals and signal relay devices for State Grid Changji Electric Power Supply Company are 850 and 900 MHz models. The signal formats that are supported by IoT devices are changed when 2G low-frequency signals are eliminated from the network. The frequency band will be unable to search for signals or register with the network, resulting in widespread device failure. This paper analyzes the performance of current IoT devices and the supporting network situation based on the analysis of the existing wireless public network signals in the basement, and then offers a wireless public network signal solution under current working conditions for reference by relevant personnel.