A Portable Power-efficient PM2.5 Sensor System

Abstract

Since the atmosphere has been highly polluted over the recent years, more and more people start to take this subject seriously. The toxic substances adhering to the particulate particles can enter the human bodies as they breathe, and thus cause the body health damage, especially for the particulate particles with a diameter less than 2.5um (PM2.5). Many gas sensor systems are therefore proposed to monitor air quality recently. Although these existing PM2.5 sensor systems can be deployed and acquire PM data correctly, they lack of the portability due to usages of the external power supply or an external battery. Currently, there are no PM2.5 sensor systems that can support the interfaces of micro-USB and Apple lightning with mobile phone since the PM2.5 sensor system usually consumes more power than that the mobile phone can provide. In this paper, we propose a PM2.5 sensor system named PaS-PM2.5 that can support the micro-USB and lightning interfaces for the mobile phone. The PaS-PM2.5 adopts the energy storage hardware mechanism and a low power firmware technique to enable the use of mobile phone power, while a sensor calibration method can acquire the accurate PM2.5 concentration. With the low power support of hardware and firmware mechanism, the sensor system can achieve 32% reduction of power consumption and thus meet the limitation of the mobile phone power supply. Furthermore, the PM2.5 mass concentration of our proposed low power sensor system has 98.04% of R-squared (R2) as compared to the sensor system without the low power mechanism.