Localization with a Mobile Beacon in Underwater Sensor Networks

In underwater sensor networks, localization is one of the most important issues because sensor nodes are considerably difficult to be deployed at determined locations. Since range-based schemes require additional device and precise time synchronization for measuring distances in underwater environments, range-free schemes are promising in the view point of energy consumption and implementation. Coarseness of range-free schemes in the localization accuracy can be compensated utilizing a mobile beacon. In this paper, we propose a new range-free localization scheme with a mobile beacon which estimates two candidates for the location of a sensor node utilizing geometry and then determines the final location out of the two candidates. During simulations, the proposed scheme was indeed shown to provide higher localization accuracy with respect to irregularities in acoustic range.