A New Sequence-Based Iterative Localization in Wireless Sensor Networks

Abstract

In wireless sensor networks, the localization space can be divided into distinct regions that can each be uniquely identified by sequences in traditional sequence-based localization (SBL). The sequences represent the ranking of distances from the reference nodes to that region. But the average estimate error for locations in a face region is quite in evidence. For the problem of location error, a new localization technique which is an improvement of SBL is proposed here. It uses the triangular area enclosed by the centroids of the three "nearest" location regions to exclude areas in which the unknown nodes do not exist, so it will narrow the range to some extend and then improve the accuracy of localization. Then the new localization chooses the centroid of the triangular represented as location estimate of the unknown node, at last it regards the unknown node as a reference node and locates the next unknown node iteratively. The new localization technique will bring some computing increases, however it does not need additional improvement in hardware or complexity of nodes. Simulation experiments prove that the new localization provides comparable or better accuracy than SBL and the centroid method. If the proportion of reference nodes increases, the location error will decrease markedly.