Iterative location algorithm based on adaptive grid

How to obtain the unknown nodes´ position is an important issue in WSN research fields, in which ranging error and position of beacon nodes´ have a great influence on the accuracy of localization. In this paper, an iterative location algorithm based on adaptive grid is proposed. By putting the beacon nodes on the edge of the unknown nodes´ distribution area, the cosines theorem of triangle is used to obtain the unknown nodes´ coordinates. Then, some optimally located nodes are selected as new beacon nodes (called NBNs). According to these NBNs´ coordinates and their communication range, next grid´s width or height is calculated. By repeating this iterative process, all the unknown nodes will be located gradually.