Smart Multi-mode Networking Architecture Using NB-IoT and LoRa with Bi-direction Communication Function for Remote Monitoring Applications

Wired communication is characterized by high reliability and stability; however, it is difficult to string and has a limited placement area in IoT devices. Wireless communications are characterized by high deployment flexibility; however, their transmission performance is easily affected by weather conditions, electromagnetic waves, obstacles, and other factors. To maintain the transmission advantages of the above two and resolve the signal instability or interruption that often occurs when using single-mode communication transmission, this study proposes a smart multi-mode networking architecture using NB-IoT and LoRa with a bi-directional communication function. Multi-mode communication nodes (MMCN) can intelligently and automatically switch to different wireless communications (such as 4G, NB-IoT, or LoRa), according to the current transmission environment. An MMCN can also be used with a multi-hop wireless network (MWN) to transfer data packets between end nodes and relay nodes to increase the transmission distance of the networking architecture. The MMCN was deployed in experimental environments to explore the relationship between the transmission performance of the MMCN and weather conditions, temperature, deployment locations, and obstacles. The results showed that the packet loss rate could be reduced by 6% during heavy rain, and the radius of the transmission range beyond the base station signal coverage could be increased by more than 1 km. This indicates that the system is robust and can be used in various applications.