An Iterative Method of Processing Node Flip Ambiguity in Wireless Sensor Networks Node Localization

In order to solve the problem of the node flip ambiguity generated by using classical least squares method in wireless sensor networks node localization, an iterative method based on triangular node blocks (IP-TNB) to process node flip ambiguity is proposed in this paper. At first, orthogonal projection detection method is adopted to detect an unknown node needed to be positioned. If the node would be detected to have a flip ambiguity, based on the stability of triangle node blocks and the whole network connectivity information, the flip ambiguity node is processed by the iterative method based on coordinate transformation and recursive optimization, so the process can detect and correct the problem of node flip ambiguity using the least squares method. The simulation results demonstrate that IP-TNB has better positioning performance and reduce node localization errors compared with Particle Swarm Optimization (PSO) and Iterative Inflexible Body Merging (IIBM) proposed by Xiao et al. By the simulation experiment of the effect of the number of beacon nodes and range errors on IP-TNB, results show that the proposed method not only can effectively deal with the problem of node flip ambiguity using the least squares method, but also improve the whole network localization accuracy.