The Intelligent And Wireless Household Gas Alarm System Based On ZigBee Technology

In this paper, according to the practical application and social research needs, designing a household gas alarm system based on ZigBee wireless networking technology. The system makes CC2430F128 as the controlling and processing core, basis to zigbee2006 protocol, starting Z-stack protocol to build network, terminal nodes in this network can be added and certificated to the network. The terminal node of the home real-timely gets leaked gas concentration, and sends the data to the higher level routing node or the central coordinator. Center coordinator connected PC with the serial port. In the host computer monitor; you can monitor the leakage gas concentration of each node of network and other important parameters of wireless communication. Setting two alarm thresholds by software, first alarm threshold value as a buffer to wait for the alarm system is stable with sound and light alarm, second alarm using the public network telephone call advance fixed voice telephone numbers. The main research topics are as follows:The hardware circuit design of center coordinator and ZigBee end device are done. Taking into account environmental factors to the terminal nodes, so, join design of the battery power and MCP1259 low pressure detection and alarm. These do well in ensuring smoothly set up the network.Designing hardware circuit of voice module, recording corresponding alarm voice, starting to play it after phone alarm, Packaging the microcontroller and the telephone interface chip, and compiling a complete serial port AT command protocol to facilitate the external processor control.Designing circuit of Sensor data acquisition and the sensor signal condition circuit, calibrating the combustible gas sensor and the sensor signal condition circuit, making the concentration of the collected data into 1 ~3V voltage output.Applying ZigBee-2006 protocol standard to building mesh-like network,and allowing devices of the same frequency signal certified and joined the network within the coverage area. Certified nodes are resisted and managed, distributed network address, and makes the network address matched with geographic infor-mation to facilitate alarm.Designing PC monitor interface. PC monitor interface is written by VB6.0 software, receipt and show each node of network show the concentration of data, draw Real-time rendering of each node in the relevant concentration curves.