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Design of Air Quality Monitoring System Based on NB-IoT

A air quality monitoring system based on the NB-IoT was designed for wireless monitoring of special field environment. The STM32FI03RCT6 microprocessor unit was the core processor and the data of gas pollutants was collected by electrochemical gas sensor through serial port. The switching mechanism of wireless network and the data storage mechanism of disconnected network was designed. The network communication based on the TCP/IP protocol was realized through NB-IoT module or GPRS module. The experimental results show that the data transmission of NB-IoT network is stable. The system can automatically switch to GPRS network as the NB-IoT network is abnormal. In the absence of network, the data is stored in SPI Flash. The collected data can be reloaded as the disconnected network is recovered.