A localization Approach for Sensor Networks by Using Round Trip Time

Abstract

Node localization is a crucial requirement in wireless sensor networks (WSNs). Localization is known as the estimation of the precise physical location of the sensor node. The position of each sensor node in WSNs could be determined by attaching GPS to each node or manually by a human, but both of these are unrealistic in large WSNs due to cost and human efforts. Round trip time (RTT) is one of position estimation methods in WSN for assisting sensor nodes in determining their location. This paper proposes an approach to get a precise estimation of the distance between sensor nodes for one of the aspects of self-management, which is self-locating. The proposed approach presents an algorithm to refine the measurements. Different factors that affect the measured RTT values are studied. Furthermore, the results of two ways of estimating distance are discussed, simulated and evaluated. Finally, the simulation results show that considerable improvement in localization determination can be achieved with the proposed method.