Research And Application On Rssi Localization Algorithm For Wireless Sensor Network

With the rapid development and maturity of the microelectronic technology and the wireless communication technology, the wireless sensor network emerge as the times require, which has sensing, computation and wireless communication capabilities. The wireless sensor network is widely used in traffic management, environment monitoring and other fields. And the localization technology is the basis and premise of target recognition and tracking, personnel positioning and many other applications. Therefore, the research of the localization technology for wireless sensor network has important theory significance and practical value.The basic idea of the received signal strength indication(RSSI) based localization approach for WSN is to determine the distance by calculating the signal transmission loss, then locate the node of interest. This algorithm is vulnerable to environmental factors and experiences low positioning accuracy. According to improving both location precision and localization algorithm, a high accuracy positioning algorithm is proposed in this paper. Besides, the software design of positioning system is completed and the algorithm is applied to the actual location system. The main research and innovation points of this paper are listed as follows:1. Concerning the ranging method, the accuracy is improved. First, the propagation loss model is obtained in specific environmental by experimental calculation and improved by the weighted least squares method. Then, an improved extended Kalman filter method is proposed to improve the accuracy of positioning by changing the iterative process of the Kalman filter. Finally, the simulation is given to demonstrate the effectiveness of the proposed algorithm.2. Starting from the location algorithm, the accuracy is improved. Three effects on location accuracy of trilateration are analyzed in terms of the quality of location unit, the distance between label and node and the position of label. The weighted fusion positioning algorithm is proposed to improve the positioning accuracy. Finally, the simulation indicates the superiority of the proposed algorithm by comparison with the traditional location algorithm. 3. A wireless sensor network monitoring positioning system in the prison environment is designed and implemented, which has the functionality of achieving node precise positioning and displays the node position in real-time. The practicality of the system can be executed by the demonstration of the positioning system.