基于RFID读写器网络的粮库温湿度分布式监测

Temperature and humidity distributed monitoring for grain depot based on RFID reader networks

针对粮库粮情参数监测点多、通信距离远、系统扩展和移动性能差的现状,提出一种基于3级读写器网络的粮库温湿度无线监测系统。集成温湿度传感器SHT75、主控器MSP430F149及射频通信模块NRF905设计了一种RFID传感标签,分布在粮库内实时采集标签周围粮食的温湿度信息;前端读写器无线接收传感标签的温湿度信号并将其与时间及地址编码信息打包,中继读写器无线接收前端读写器的粮情信息并无线传输给终端读写器和中央监控计算机。试验表明,系统具有功能扩展方便、传输距离远(有效通信距离≥128m)、路由选择与定位简单等特点。

As the monitoring system for grain depot has the characteristics of multiple measuring points,far transmit distance,poor expansion and hardly mobility,a new method using three layer reader networks for wireless monitoring the temperature and humidity of grain depot was proposed.A sensor-tag integrated with the sensor SHT75,the microcontroller MSP430F149 and the RF communication module NRF905 was designed.The temperature and humidity signals of the grain depot were acquired by sensor-tag,packaged with the current time and the address code information by front-side reader,and transmitted wirelessly to the terminal reader and control center by relay readers.The experimental results show that the system has the characteristics of good expansibility,long transmit distance（≥128 m）,simple routing and easy positioning.