Design Of Home Environment Monitoring System And Research On Node Localization Based On Zigbee Network

With the progress of science and technology, especially the improvement of people’s life quality, there is an increasing demand for smart home, especially the rapid development of Wireless Sensor Network which is one of the main trends in the development of new technology in the world. It combines many kinds of advanced technologies and has important commercial value and scientific research value, has a wide range of applications such as the internet of things, monitoring of agricultural ecological environment, medical care and other fields, directly promote the development of smart home. Wireless communication is realized by using the ZigBee technology in wireless sensor networks. Because it has the advantages of low cost, low power consumption, reliable performance of ad hoc networks and network. With the ZigBee technology, smart home system comes to be different from the traditional household whose drawback are wiring complicated, heavy workload, high cost, difficult maintenance, shortcomings, easy networking, etc. So it is the first choice of communication technology as a smart home application technology.This paper designed a home environment monitoring based on wireless sensor network, including acquisition of sensor data and precise arbitrary control of multiple LED lights. The sensor is mainly connected with the ZigBee terminal, which is used to collect indoor temperature and humidity information, smoke information and light information. This information is transmitted to the coordinator through the ZigBee wireless sensor network. WiFi serial port server is connected with the coordinator through the TTL to RS232 interface and sends WiFi signals, so that Sensor data collected by the coordinator can be received through the mobile terminal (mobile/PAD) to receive and display in the software interface. In turn with this design, the precise control of each ZigBee terminal node LED lights in the mobile terminal software interface. Finally, the system realizes the bidirectional circulation of the whole network.This paper takes the exploration and research for the wireless sensor network node positioning algorithm in addition to focusing on the related content of the smart home, ZigBee key technology introduces several commonly used positioning algorithm. This paper introduces several common location algorithms and proposes a new algorithm based on the improved RSSI node localization algorithm Bayesian probability statistical model, which have higher accuracy and greater stability than traditional values RSSI Location Algorithm. This algorithm first uses the Bayesian probability model to select the part of RSSI value. Then the unknown node coordinates are solved by the triangle centroid algorithm. Finally coordinates value obtained needs to be taken many times of iterative refinement operation and achieve optimal solution of the position coordinate to get the final coordinates. Simulation results show that the proposed algorithm has a great improvement in accuracy and stability compared with the traditional RSSI algorithm. And when the anchor node proportion is low, the algorithm performance is still very good.