A Lightweight Localization Scheme in Wireless Sensor Networks

Localization is an important topic in wireless sensor networks because sensor nodes are randomly scattered over a region and they get connected into network on their own. Many localization algorithms have been proposed. These localization protocols can be divided into two categories: range-based and range-free. The range-based techniques use distance estimates or angle estimates to achieve fine accuracy with expensive specific hardware. In the other hand, the range-free mechanisms depend on the contents of received message to support coarse accuracy. In this paper, we present a lightweight range-free localization scheme using mobile anchor nodes. The anchor node equipped with GPS broadcasts its coordinates to the sensor nodes as it moves through the network. As the sensor nodes collect enough beacons, they are able to calculate their locations locally. Simulation results show that the proposed scheme achieves best performance in percentage of localized sensor nodes without many mobile anchors..