Energy-efficient localisation of sensor nodes in WSNs using single beacon node

Identifying the location of randomly deployed sensor nodes in wireless sensor networks (WSNs) is a major challenge because sensor nodes have limited energy and computational capacity. This study presents a low complexity, scalable, and energy-efficient localisation scheme capable of localising dense as well as sparse deployment of nodes using a single beacon node (SBN). The nodes act in passive listening mode to receive information transmitted by the SBN to determine their locations. The energy consumption is reduced at the nodes as well as at the SBN. The SBN has an omni-directional antenna and a directional antenna (DA). DA can rotate to transmit beacons in different directions in the XY-plane. The time required and energy consumption for localisation are reduced at the node side as well as at the SBN side. The expressions for energy consumption and computational complexity are deducted analytically. The proposed scheme is verified with MATLAB simulation. The simulation results show a significant improvement in localisation accuracy and reduction in energy consumption.