Research On Node Localization Algorithm Based On RSSI In Wireless Sensor Networks

The sensor nodes’ location information not only has a great significance to its application, butalso plays an important role in the network’s function.This paper has studied the Received Signal Strength Indicator method and the Shadowingmodel, the main contents are as follows:In order to suppression the impact of the signal measurement RSSI value to the RSSI averagevalue. The data which had a large measurement error was weeded out by the threshold valuewhich was determined by the Gaussian distribution function, and calculated the RSSI average valueby introduced a coefficient. The result shows that it has a better suppression effect than theGaussian filtering algorithm.According to if the signal model adopted a unified parameter throughout the region that wouldmakes a major error, this paper has proposed an algorithm that estimated the actual value of theparameters in the vivacity of the unknown node by the anchor node which were involved inthe position calculation. It was turned out that this method had a lower positioning error.The distance between the unknown node and the anchor nodes was the key to the WeightedCentroid algorithm, a new algorithm which calculated these values by using the distances and theRSSI value between the anchor nodes was proposed, then sorted these distances in anascending order, selected the first five value, and took any three anchor nodes to form a triangle,then judged whether the unknown node was in the triangle’s internal by the PIT algorithm. It wasturned out that this method had a lower positing error than the distance-Weighted Centroidalgorithm.