A Localization Algorithm nin Wireless Sensor Networks Using a Mobile Beacon Node

Wireless sensor networks is one of important information acquisition methods and also has been a promising technique for many applications in recent years. Node localization is one of challenging and fundamental topics in distributed WSNs research. The goal of this paper is to propose an efficient range-free localization algorithm in WSN. We use directional antennas other than omnidirectional antennas. While the mobile beacon node using several directional antennas moves, it periodically broadcasts its packet in K directions. Ordinary sensor nodes are able to estimate their position based on the messages received from only one virtual beacon. We also use discrete imprecision range measurement. It can send messages in different lever of power to obtain the approximate distance between neighbor nodes. Considering WSN is an event-based network, we propose a refinement phase in latter part of this paper. The main advantage of the algorithm is that it is both simple and economical. Our simulation has shown that the given approach is able to provide accurate and robust estimation of sensor location.