A kind of nodes localization method for three-dimensional UWSNs

Node localization is a research hotspot in underwater wireless sensor networks (UWSN) because most applications are based on geographical position of nodes. Currently, most of node localization methods are based on the two-dimensional space and could not meet the requirement of location accuracy. A three-dimensional node localization method was proposed based on a ranging technology named RTOF (round-trip time of flight) and an improved PSO (particle swarm optimization) algorithm, which can calculate distance between nodes without time synchronization and locate the nodes in three-dimensional space directly. The localization errors of the proposed method were compared with the Least Square method and standard PSO algorithm by some simulations. The results indicate that the proposed method can improve localization accuracy without increasing hardware complexity, system cost and communication power consumption.