Low Cost Air Quality Monitoring System Using LoRa Communication Technology

This paper proposes a low cost air quality monitoring system using LoRa-based communication technology. The proposed system consists of several sensor nodes and a gateway. Sensor nodes read pollutant levels in the air using the MQ-7 sensor for CO gas, MQ-135 for CO2 gas, GP2Y1010 for Particulates Matter (PM) and the DHT-22 sensor to read air temperature and humidity. Arduino UNO R3 is used as the data processing centre. Sensor data is sent to the gateway using the LoRa RF96 module. The gateway forwards the sensor data received to the Thingspeak server using NodeMCU V3, and users can access it via the internet network. The test results show that the designed system could read the levels of pollutants in the air and sent them to the Thingspeak server. Indoor-placed gateway could receive data from outdoorlocated sensor node with a 100% success rate up to a distance of 32 meters. While at a distance of 50 meters, the success rate of data reception by the gateway was 99.17% and at a distance of 70 meters was 78.3%.