MAIL: Multi-Hop Adaptive Iterative Localization for Wireless Sensor Networks

The paper presents a multi-hop adaptive and iterative localization (MAIL) algorithm for localization wireless sensor network (WSN) nodes. The present study determines the uncertainty in the localization of nodes caused by the variation in the received signal strength or in the angle of arrival of a signal received by such nodes. An iterative localization algorithm is then proposed to decrease this uncertainty through iterative message exchange and subsequent modification of the uncertainty region. A single anchor based network with randomly deployed nodes is considered. The anchor node communicates its position to its neighbor nodes through directional antenna. The node determines its possible location area through the angle of arrival, received signal strength and the location of the anchor node. It transfers this information to its neighbors. Each neighbor determines its location area depending on the received information. Multiple iterations of this process are used to decrease the region of uncertainty. The paper presents the concept, algorithm and simulation results. The results clearly indicate the improved efficiency of proposed multi iterative algorithm in comparison with existing algorithms. The algorithm is optimized towards using minimal computational power at the nodes. The simulation results show that the uncertainty region of localized nodes is reduces significantly with the increase in the number of iterations and the propagation of associated estimation error is minimal.