Range-free node localization in multi-hop wireless sensor networks

To localize multi-hop wireless sensor networks (WSN) nodes, only the hop-based information (i.e., hops' number, average hop size, etc.) have been so far exploited by rangefree techniques, with poor-accuracy, however. In this paper, we show that localization accuracy may greatly benefit from joint exploitation, at no cost, of the information already provided by the forwarding nodes between each anchor (i.e., position-aware) and sensor nodes pair. As such, we develop a novel rangefree localization algorithm, derive its average location estimation error (LEE) in closed-form, and compare it in LEE performance with the best representative algorithms in the literature. We show that the proposed algorithm outperforms in accuracy all its counterparts. In contrast to the latter, we further prove that it is able to achieve a LEE average and variance of about 0 when the number of sensors is large enough, thereby achieving an unprecedented accuracy performance among rangefree techniques.