A Novel Self-Adaptive Localization Scheme in Wireless Sensor Networks

Node localization problem is crucial to many applications in wireless sensor networks (WSNs).A lot of researches have been done in finding range-based and range -free methods for localization in WSNs. Range-based methods estimate location more precisely than range-free methods. However, range-free methods are cost-effective and simpler to implement for resource constrained sensor nodes. In this paper, a novel self-adaptive localization scheme that combines range-based (RSSI) and range-free (DV-hop) algorithm for wireless sensor networks is proposed. First and foremost, we decide to make use of the RSSI or DV-hop according to the numbers of neighbor anchors; Secondly, in order to improve the accuracy of localization further, we need to choose some appropriate anchor nodes; Finally, the virtual anchors are utilized to improve the numbers of anchor nodes, which can enhance the efficient localization for the position nodes when the original anchors are sparse. This algorithm can not only combine the range-free and range-based advantages, but can locate nodes for nodes density sparse networks more effectively and enhance the localization accuracy.