Study On Three-dimensional Localization Method Based On Mobile Anchor In Wireless Sensor Network

In recent years, Wireless Sensor Network(Wireless Sensor Network, WSN) plays more and more important role in intelligent medical care, environmental monitoring, military reconnaissance and so on. The applications of WSN in many fields cannot leave the node location positioning. Without the location information, Data sensed by WSN has lost its meaning. The current research on the positioning technology of WSN mainly concentrated in the two-dimensional plane, while the distribution of the sensor nodes in real environment is mostly in 3D scene, in this case, the high precision, low cost and low energy consumption of wireless sensor network node location technology in three dimensional space and refinement method have became one of the most important direction of WSN researches in recent years.First of all, the article introduced the background, significance and support key technologies of WSN network after reading large amount of books, documents related WSN location technology and then elaborating wireless sensor positioning technology and development situation at home and abroad, especially expounding the positioning technology of the typical positioning model and algorithm. At the same time, I introduced the related concepts, performance index and classification of positioning technology.Second, The positioning precision of positioning technology largely depends on the density of the anchor nodes in WSN network, and the number of anchor nodes directly determine the costs of the network. In addition, research at home and abroad mostly stays in the two-dimensional plane, while under the three dimensional space positioning technology research is not enough. In this paper, I have a through understanding on the mobile anchor node auxiliary positioning technology under the three-dimensional space, and propose my own algorithm: Under the 3D scene based on RSSI ranging and using mobile anchor nodes auxiliary localization algorithm, and using mobile anchor nodes according to the mobile trajectory so that it can effectively solve not only three-dimensional positioning, but also the environment of less anchor node location problem of the unknown node.And then, RSSI ranging hardware requirements are low and positioning accuracy is higher than other methods. But RSSI ranging which relies on the strength of the sensor nodes receiving signal to realize positioning. It is more easily interference by some environmental factors, which caused the location information is obtained by RSSI ha d certain problem. In this article, I studied and researched the ranging principle, influencing factors and its improved algorithm in depth, and optimized the RSSI value correction on the basis of the ERSS algorithm. RSSI values which meet the conditions for ERSS were disposed through the weighted centroid algorithm and extended kalman filtering processing to realize the optimization of RSSI and improved the positioning accuracy.In the end, I built a public platform which can be applied to a variety of the algorithm through the Matlab program. Through the simulation, the improved algorithm is better than the traditional positioning methods in positioning accuracy, execution time, network coverage and other aspects.