Scalable and distributed GPS free positioning for sensor networks

Accurate positioning mechanisms are important in large scale sensor networks to achieve a number of functionalities like location aware routing, efficient coordination of resources and other application specific requirements. This paper proposes a distributed and scalable GPS free positioning algorithm for wireless sensor networks. This approach is an effort in the direction of finding a solution to the positioning problem which minimizes the number of messages exchanged and the coordinate setup time. We use a clustering based approach for the coordinate formation wherein a small subset of the nodes can successfully establish the coordinate system for the whole network. We also compare the performance of this system against existing mechanisms and show that our system scales linearly as the number of nodes in the network increases in contrast to the exponential increase in current mechanisms. Additionally, our mechanism takes considerably lower convergence times. The proposed mechanism is scalable, distributed and able to support the ad hoc deployment of large scale sensor networks quickly and efficiently.