A Range-free Node Localization Algorithm Based on Potential Space Self-definition and Local Neighbor Selection in WSN

A range-free 3D node localization algorithm based on potential space self-definition and local neighbor selection in Wireless Sensor Network (WSN) is proposed in this paper. This algorithm needs only three anchors in space without extra information exchange between unknown nodes and position estimation is completed by using triangle method. Only three anchors are placed in the specified positions of a cube space in advance, named as A1, A2 and A3. Unknown sensors will compute the minimum hop counts to A1, A2 and A3 respectively and a potential sub-space will be defined whose hop counts are the same in which unknown sensors may most possibly locate. By using this sub-space the positions of unknowns will be computed roughly and then more accurate position estimations will be given according to its other local neighbors in the adjacent potential sub-space which is called local neighbor selection. Simulations are finished in MATLAB to explore the effects of different parameters on the proposed method and it is proved this method has better robustness and stability in extremely bad environment. Also comparisons are made with classic DV-Hop method and the results prove the proposed algorithm is better than the DV-Hop method in localization accuracy.