Based on the cyclic refinement APIT localization algorithm for wireless sensor networks

Self-positioning of sensor nodes is one of the important research in the wireless sensor networks. APIT is a major non-ranging-based localization algorithm. Relative to other non-Ranging-based Localization Algorithm, APIT has a high positioning accuracy, communication overhead, and so on. However, APIT algorithms require higher density neighbor anchor node, For those neighbors around the anchor nodes, all of the neighbors is less than 3 or the triangle composed of anchor nodes is not the external triangle of the unknown node, The of APIT algorithm will not useful. In this paper, for the defect,added the cycle refinement to the APIT algorithm, and set of adaptive weights and thresholds. By the simulation results, the positioning effect has been greatly improved.