Hierarchical air quality monitoring system design

Beijing in China is facing a serious air pollution problem which severely impacts the daily life quality. How to monitor the air quality in real-time with a big coverage of Beijing city, and automatically process the big data is now becoming a hot research topic. Air quality sensors, such as CO, SO2, NO, NO2 and PM2.5 sensors, can accurately detect the level of air pollution which may contain different kinds of tiny particles. By using Internet of Things (IOT) technology, information can be transferred from IOT sensor nodes to the information processing center through different wireless/wired networks. This paper aims to build a prototype system by hierarchically deploying terminal sensor nodes inside the smart buildings of each floor and data collection units and routers in the open spaces between smart buildings, and transferring the sensor thing data back to the information processing center for real-time display. In this implementation, all sink nodes send out air quality detection information to the information processing center through Zig-Bee wireless protocol. Information processing center receives and analyzes real-time information being collected from the sensors, stores all information to the database. Through reading IOT thing data stored in the database, web front-end system will draw real-time, high-quality air quality monitoring maps of the inside and outside of the buildings. Further, a detailed system power optimization is also presented.