Positioning algorithm for underground wireless sensor networks based on node mapping

In view of problem that unknown nodes out of the region of anchor nodes are not considered with current underground positioning algorithm, which leads to bigger positioning error, an improved weighted centroid positioning algorithm based on node mapping was proposed. The algorithm conducts node mapping process for unknown nodes out of the region of anchor nodes, gets multiple centroids of anchor nodes by improved weighted centroid positioning algorithm, and uses multiple centroids to position unknown nodes. The simulation results show that the improved algorithm can improve positioning accuracy of nodes.