Research On Localization Methodology In Wireless Sensor Networks Under Beacon Drifting Scenes

Localization problem is one of the key supporting technologies in wireless sensor network.In most cases, people set some sensor nodes with pre-set location as beacon nodes, and calculate the location of other sensor nodes without pre-set location from the observations with the beacon nodes. These beacon nodes are usually assumed to be strictly reliable. It is the prerequisite of the accuracy of all localization methods with beacon nodes.The problem of drifting beacons is defined as the problem in the case that the beacon nodes may change their position due to human or environmental factors accidentally. In this case, due to the accidentally position change of some beacons, the localization result of other nodes in the network will be affected or even cannot be located.The main research of this paper is as follows:①A distributed drifting beacon node detecting mechanism is introduced in this paper. This mechanism enables the network detecting drifting beacon nodes automatically with self-scoring and consultation methods.②After detecting of the node localization, an improved localization method is introduced against the localization coverage decreasing situation under beacon drifting scene. It use2D probability density model to describe the localization reliability, and use this as a basis to upgrade some normal nodes as temporary beacon nodes around the localization blind areas. ③Simulation is applied to evaluate the reliability and the resource consumption of the mechanism. Simulation result shows that the drifting beacon detecting mechanism introduced in this paper has good performance and consumes less network resource, the localization methodology based on localization reliability model can provide better coverage and accuracy of localization under beacon drifting scene.