A Grid-Based Localization Algorithm for Wireless Sensor Networks Using Connectivity and RSS Rank

Abstract

To improve localization accuracy and reduce system costs, a new range-free localization algorithm for wireless sensor networks using connectivity and received signal strength (RSS) rank is proposed. An unknown node is first localized in an initial residence area according to the connectivity constraints. Then, the residence area is refined using the RSS rank vector. The RSS rank vector of an unknown node is formed from the ranks of the RSS values obtained from neighboring anchors. The estimated location of the unknown node is the centroid of the refined residence area. The proposed localization algorithm uses a grid scan approach to avoid the complex geometric computations. This algorithm is improved by using an adaptive strategy to determine the grid size. The performance of these methods is examined via analysis and simulation. The results obtained verify that the proposed approaches provide better localization accuracy than competing algorithms in the literature.