Design And Research Of Multi-channel Wireless Gas Sensor Detection System

Gas sensor detection system is effective tools for collecting and processing sensor signals. Most of traditional gas detection system base on PC-type system or single model embedded system. Faced with increasingly complex measurement environment, and the rapid developed micro-system technology and wireless communication technology merging into detection system, a variety of new wireless intelligent gas sensor detection systems are coming into being. Based on the above background, this paper presents a kind of distributed wireless detection system for resistive type semiconductor gas sensor.The detection system designed in this paper applies master-slave distributed architecture: has only one system control terminal, as a host; has many acquisition nodes, as slaves. Acquisition nodes and system control terminal communicate by wireless means. The hardware used low power, good performance NRF24L01 chips. Communication standards used custom communication format. And the whole system constitutes a point to multipoint communication platform. Acquisition nodes with low power MSP430 microcontroller as its core, is responsible for collecting sensor data accurately. Control terminal with ARM9 processor as its core and embedded Linux operating system as its platform, is responsible for receiving sensors data, adjusting the acquisition node mode and parameters, and integrated treatment of sensor data. We control the system and sensors data display mainly through the 3.5-inch LCD touch screen. This paper has developed a comprehensive control program based on QT to achieve this functionality.The gas detection system this paper designed captured sensor signal accurately, and after the actual test, acquisition sensor signal error is less than 1%; System communication is stability and reliability. Error rate can be achieved 10-5-10-6 and in the case of no obstacles interference, effective communication distance can be achieved 100m; Having good man-machine interface, and users through the embedded control terminal can view current gas sensor singals and control the detection system; The system provides a platform for studying the characteristics of gas sensor and gas sensor practical application, and now the laboratory has been using this detection system.