Efficient range-free localization algorithm for randomly distributed wireless sensor networks

In this paper, we propose a novel range-free localization algorithm able to reduce errors due to mapping the hops into distance units. Using the proposed algorithm, the mean hop size h̅_s is locally derived at each regular or position-unaware node, thereby avoiding its broadcast by anchors (i.e., a few nodes aware of their exact position) as usually required in current state-of-the-art solutions and, hence, resulting in less battery power depletion. The analytical expression of h̅_s is derived for different node distributions. Furthermore, it is shown that it is possible to locally compute h̅_s at each regular node with or even without prior knowledge of the node distribution. Simulations results show that the proposed scheme outperforms the most representative range-free localization schemes in terms of accuracy.