Pascal's triangle-based multihop range-free localization for anisotropic sensor networks

This paper presents a multihop range-free localization algorithm to enhance the localization accuracy in anisotropic networks with a small number of anchors. We derive potential locations of a normal node and corresponding probabilities in terms of the average one-hop internodal distance, the average hop progress and the hop counts to anchors. A novel distance estimation based on the potential locations is proposed to tolerate network anisotropy from nonuniform node deployments, irregular regions, and irregular radio simultaneously. Compared to other range-free algorithms, the proposed algorithm requires fewer anchors while achieving higher localization accuracy. The superiority of the proposed algorithm against other algorithms is demonstrated through computer simulations.