A multi-hop PSO based localization algorithm for wireless sensor networks

A sensor network consists of a large number of sensor nodes that are distributed in a large geographic environment to collect data. Localization is one of the key issues in wireless sensor network researches because it is important to determine the location of an event. On the other side, finding the location of a wireless sensor node by the Global Positioning System (GPS) is not appropriate due to some limitations on sensor nodes such as price and physical size. In some localization approaches, sensor nodes specify their position with the help of anchor nodes, which have pre-configured positions. Due to error, low accuracy of distance detection method, and, most importantly, and the multi-hop distance of the sensor nodes from the anchors, the obtained position may not be accurate. In this paper, a distributed Particle Swarm Optimization (PSO) algorithm is proposed to estimate the position of the sensor nodes using anchors. In the proposed approach, the average hop length and the number of hops between a sensor node and the anchors are used to determine the estimated positions. The simulation results, as well as the comparison of the proposed algorithm to others, in terms of the average localization error, indicate that our approach leads to more accurate localization.