Abstract: The standby replacement device plays a vital role in ensuring continuous and stable operation of automatic air monitoring stations in radiation environment, and addressing the issue of discontinuous monitoring data caused by station disconnections. The hardware design of the device includes a data acquisition system and communication system, supporting conventional serial ports, RJ45 Ethernet ports, USB, and other interfaces. The software modules comprise three components: data acquisition, data reporting, and data re-transmission. Data are encrypted and uploaded to the national data center and provincial data centers via a VPN (Virtual Private Network). Dual-mode communication ("Wired Broadband" and "4G/5G Wireless Network") is employed for communication with provincial center servers. The reporting communication adopts the TCP protocol via sockets. A mechanism for re-transmitting missed data is established within the data reporting and data re-transmission modules to ensure the integrity of reported data. Tests conducted in Mohe (Heilongjiang), Shigatse (Tibet), and Sanya (Hainan) demonstrate that the standby replacement device operates stably and reliably, effectively enabling buckup data re-transmission for radiation environmental air monitoring stations.

Key words: radiation environmental monitoring, automatic monitoring station, standby replacement, data re-transmission