Distributed Efficient Node Localization in Wireless Sensor Networks Using the Backtracking Search Algorithm

Abstract

The localization problem arises from the need of nodes of a wireless sensors network to determine their positions without the use of external references, such as the Global Positioning System – GPS. In this problem, the node location may be established thanks to distance measurements to existing reference nodes. Reference nodes know their respective positions in the network. In the search for efficient yet accurate methods to determine node locations, some bio-inspired algorithms have been explored. In this sense, targeting a more accurate solution of the localization problem, we propose a new multi-hop method based on the Backtracking Search Algorithm. It includes a new technique to assess the confidence that should be granted to a contribution received from a neighboring node, and hence incorporating it into the localization computation accordingly. The achieved performance results prove the effectiveness of the proposed method as well as the efficiency entailed by the confidence factor assessment technique. The impact of the latter is more evident when the number of reference nodes in the network is reduced. This constitutes a very big advantage with respect to state-of-the-art localization methods.