A Range-Free Localization Algorithm in Concave Areas

Large amount of range-free localization algorithm are depended on sensor nodes densely deployed in an isotropic area. The study of localization problem is in the precondition of a mapping function between measured distance and Euclidean distance for pair of sensor nodes. If the sensors are deployed in an anisotropic network such as concave area, traditional assumption of isotropic sensor network will not hold. In this paper, we study the problem of localization algorithms in anisotropic sensor network, and propose a range-free localization method WSAN (weight-based selective anchor nodes localization algorithm) used in the anisotropic networks based on each anchor´s weight. In the WSAN, all unknown nodes keep an anchor nodes´ information table recording each anchor´s weight, and choosing the anchors which are less affected by the anisotropic factors involved in the localization. The algorithm has been demonstrated that it has a lower localization error rate comparing with traditional localization algorithms; hence, making it suitable for anisotropic sensor areas.