Design Of Indoor Air Quality Monitoring System Based On Wireless Sensor Network

Air quality is an important factor affecting the health of people in the indoor environment, especially as wards, offices, classrooms, factory buildings and other sealing better, space is relatively small place, how to monitor indoor air quality has become particularly important. The basic elements of air quality include: temperature, humidity, carbon dioxide, carbon monoxide, formaldehyde, PM2.5, etc. Aiming at multiple physical of indoor air quality, the air quality monitoring system will make multi-point and real-time monitoring. The collected information is uploaded by wireless data communication network which composed by Zig Bee wireless communication module and GPRS module. The final data is displayed on the PC, and according to the set value alarm.The system uses STC12C5A60S2 series as the control center. It also includes high-precision laser detection PM2.5 sensors, temperature sensors, humidity sensors, as well as aldehyde, ketenes, alcohols gas sensor detects levels of formaldehyde in the air. To facilitate installation, the system uses a wireless data transmission network to communicate. Firstly, Zig Bee modules using enhanced chain topology to component data communications network, and the Packaging data transmission via GPRS modules to the network. According to the data displayed on the PC, we can view real-time data for each collection point. If some data exceeds the set threshold, the system will alert.The innovation of this system includes:(1)The existing environmental quality monitoring devices and wireless sensor network together can collect and transport PM2.5, temperature, humidity, formaldehyde and other information which from multi-point in the indoor environment, and according to a preset threshold to monitor each of the physical quantities.(2)According to the characteristics of sensor’s space location, the thesis proposes an enhanced chain wireless network topology, and the new topology can effectively enhance the robustness of wireless networks and avoid failure when a single network node affects the transmission of data across the network.