Distributed localization with a mobile anchor in wireless sensor networks

Localization is one of the most important issues in wireless sensor networks. Several approaches, including range-based and range-free, have been proposed to calculate positions for randomly deployed sensor nodes. In this paper, a single mobile anchor (with GPS or pre-defined moving path) is used to help sensors to accurately discover their positions. The mobile anchor periodically broadcasts its location while it moves around or through a sensor field. Each sensor nodes compute their position estimate based on the range-free technique. The effect of movement pattern to localization is discussed. The simulation results show that the scheme is a high-performance sensor positioning scheme for outdoor sensor networks.