Abstract:In order to accurately measure the concentration level of polluting gases in the outdoor environment and achieve accurate monitoring of outdoor ambient air quality, an online monitoring system for outdoor ambient air quality based on NBIoT is designed. Using the power signal output by the power supply circuit, adjust the real-time connection relationship between the microcontroller, temperature and humidity sensor, fine particle concentration sensor, carbon dioxide concentration sensor, and complete the hardware terminal platform design for online air quality monitoring. With the help of the NBIoT key text, the air interface protocol stack expression is calculated to improve the security operation mechanism of the monitoring system. Starting from the three perspectives of main function, data information collection function and monitoring task function, the main application functions in the operation process of the monitoring system are solved, and the connection relationship between hardware devices at all levels is adjusted according to the specific calculation values. Design of online monitoring system for outdoor ambient air quality. The experimental results show that under the action of the NBIoT mechanism, the online monitoring system can control the difference between the measured concentration of carbon dioxide gas and the real concentration within 3ppm under different temperature and humidity conditions, compared with the long-distance multi-channel monitoring system. , which is more in line with the practical application requirements of accurate monitoring of outdoor ambient air quality.