Abstract:  When it used non-ranging positioning method DV_Hop in three-dimensional wireless sensor networks(WSN), the positioning accuracy decreased significantly due to the complex distribution of nodes in three-dimensional space which lead to increase ranging error. In order to improve the positioning accuracy, a positioning algorithm based on an improved particle swarm optimization was proposed. It used minimum mean-square error to estimate the distance between unknown nodes and anchor nodes, and used the weighted mean square error as the optimization objective function, and used a concave function with decrementing strategy to allow particle swarm optimization access to the local search algorithm faster. It effectively raises the node positioning accuracy. The simulation results show that the positioning accuracy of the improved DV_Hop algorithm is superior to the traditional DV_Hop algorithm in the same condition.

Key words:  WSN, three-dimensional node location, particle swarm optimization, DV_Hop algorithm