Abstract: Most localization algorithms assume that communication region of node is a circular and the ranging accuracy of all anchor nodes is the same. However, in the real environment, due to signal attenuation, shadow and interference, the communication area of the node is not a regular circle. The ranging accuracy from different anchor node is also different. Therefore, PACL (Priority-Anchor node-based Centroid Localization) algorithm is proposed. First, PACL algorithm considers the irregularity of the node communication region in the localization process, and establishes the signal transmission model based on the degree of irregularity. Then, the average hop distance of anchor nodes is calculated, and the priority of anchor nodes is set according to the average hop distance of anchor node, so that the nodes with higher priority take part in the localization process to improve the positioning accuracy. The simulation results show that PACL algorithm can reduce the positioning error compared with the traditional non-ranging positioning algorithm.

Key words: wireless sensor network ( WSNs); , range-free localization; , priority of anchor node; , average hop distance; , centroid localization