Application Study Of Wireless Sensor Network In Temperature Monitoring System For Intelligent Buildings

With the rapid development of the micro-electro-mechanical systems, system on chip, wireless communication technology, integrated circuit technology, sensor technology and low-power embedded technology, the wireless sensor networks which is taken as a new kind of measurement and control network draw much attention in many research fields at home and abroad due to its low power consumption, low cost, distributed, and self-organizing. It has been widely applied in different fields such as industrial controls, intelligent building, environmental monitoring and so on.By comprehensive application of some advanced technologies such as Computer, Information and Communication, intelligent building make facilities in buildings such as air-conditioning and lighting equipment work in a harmony way. It can not only realize the intelligent control for buildings, but also have a good energy saving effects in line with the country's energy-saving emission reduction policies. In the paper, temperature monitoring system based on wireless sensor network was designed in order to realize intelligent control for buildings. The detailed structure of the paper is listed as follow:First of all, the hardware circuit of the nodes was designed. According to the function of the monitoring system, the node was divided into four modules including microprocessor control module, temperature sensor module, radio frequency module and infrared transmitter module. The major chips of the first three modules selected are MSP430, SHT11 and CC1020, and the infrared transmitter module consists of driver component and infrared-emitting diode. The circuit schematic diagram and PCB drawing were designed according to the characteristics of all the functional modules, stable hardware circuit was achieved in the last.Secondly, the software of the monitoring system was designed. With the IAR Embedded Workbench 3.41 developement kits, the programs of sensor nodes and the sink node are designed. For the sensor node, it includes programs of temperature collection, wireless transmission, Infrared Remote Control and so on. The sink node consists of some dispatch procedures in order to integrating temperature information according to the system structure and its function. On the basis of the Visual Basic 6.0 the monitoring program on the host computer was designed with the functions of database management, status display of the node, the history curve search and so on.Finally, tests of the monitoring system were processed. Placing the sensor nodes in different locations, linking the sink node and the PC with the serial port/LAN switching equipment, the temperature monitoring platform was set up in order to verify the function of the system. The experiments show that the nodes can collect real-time data and also transfer them by the wireless transmission, and the system can monitor the objects reliably. Then the subject target is achieved.The research result can be not only applied in temperature monitoring of intelligent buildings, but also other scenes which have difficulties in wiring.