Study Of Temperature Monitoring And Control System Based On ZigBee Network

In recent years, with the rapid development and integration of wireless communication technology, computer technology and sensor technology, the wireless sensor network (WSN) technology has come into being, obtaining numerous applications in industry, agriculture, everyday life and many other areas. Meanwhile, ZigBee wireless communication technology, due to its superior features of low-power, low complexity and low-cost, has attracted more and more attentions in various practical WSN applications.The combination of ZigBee wireless technology with the temperature monitoring and control technology, as well as the network intergration of the WSN and Internet, makes it possible to monitor and control the temperature anytime and anywhere. In this thesis, we construct a WSN based on ZigBee wireless technology, and connect the WSN to Internet by a GSM/GPRS module or an Ethernet module. Finally we design and realize a realtime wireless temperature monitoring and control system. The temperature measurement terminal reports the acquired information to the ZigBee gateway via ZigBee network, and the gateway, which is connected to the GSM/GPRS module or the Ethernet module through the serial RS232, sends the data to the Internet. The realtime temperature monitoring and control can then be realized by using a PC or a mobile phone. Appropriate control commands can also be sent back to the terminal through the Internet to perform corresponding adjustment and control.In this thesis, we first optimize the ZigBee network protocol based on its characteristics so that it can manage the temperature sensor nodes conveniently and report data timely. Then we complete the hardware and software design of the temperature monitoring nodes, using MSP430 microcontroller unit and SHT1X temperature and humidity sensors to perform the data acquisition and processing. The processed data is transmitted to the WSN by the CC2430 communication chip developed by Texas Instruments Incorporation. After completing the hardware and software design of ZigBee network routing nodes and gateway nodes, we finally construct a realtime wireless temperature monitioring and control system successfully and perform relative experimental tests on this system. In this system, the gateway nodes are constituted by the CC2430 chip and the GSM/GPRS communication module or the Ethernet module, while the intelligent temperature control nodes are constituted by the CC2430 chip and the MSP430 microcontroller unit. The intelligent temperature control nodes can control the temperature according to the received commands. In addition, we develop PC software, by which we can use a PC to monitor the temperature through the Internet, display the temperature curve, and set the upper and lower temperature limits. When the field temperature exceeds the threshold, the system can alarm automatically and send the warning information together with the temperature value to the terminal.The testing results indicate that the developed system can solve problems ususally occuring in the traditional temperature measurement and control process, such as the complicated wiring, widely-distributed monitoring points, difficult maintenance and poor expandability. The data transmission way makes it very convenient for users to preform realtime temperature monitoring and control. Furthermore, by changing appropriate sensors to collect specific information, this system can be easily transplanted for different applications. In one word, this system has wide applications and excellent market prospects due to its strong versatility, expandability and practicality.