Scalable and energy efficient localisation in wireless sensor networks

Abstract

A need exists for localisation algorithms in Wireless Sensor Networks (WSNs) that are scalable, energy efficient and able to function in easy to deploy sensor networks. This paper proposes a beaconless Cluster-based Radial Coordinate Establishment (CRCE) positioning algorithm to locate sensor nodes relative to a local coordinate system. The system does not make use of Global Positioning System (GPS) or any other method to provide a-priori positioning information for a set of nodes prior to the CRCE process. The objective is to reduce energy consumption while providing a scalable coordinate establishment method by focussing on the minimisation of message exchanges in a WSN. This is achieved by implementing a cluster-based network topology and utilising the processing potential of geographically distributed sensor processors together with radial coordinate propagation. Three other localisation algorithms are investigated and compared to CRCE to identify the one best suited for coordinate establishment in WSNs. The results show a significant decrease in the number of messages that is necessary to establish a network-wide coordinate system successfully, ultimately proving the CRCE method to be more scalable and energy efficient.