On optimal anchor placement for efficient area-based localization in wireless networks

Area-based localization is a simple and efficient approach, where each node estimates its position based on proximity information to some special nodes with known location, called anchors. Based on the anchors´ coordinates, each node first determines its residence area and then approximates its position as the centroid of that area. Therefore, the accuracy of the estimated position depends on the size of the residence area; the smaller the residence area is, the better the accuracy is likely to be. Because the size of the residence area mainly depends on the number and the positions of anchor nodes, their deployment should be carefully considered in order to achieve a better accuracy while minimizing the cost. For this purpose, in this paper we conduct a theoretical study on anchor placement for a very popular area based localization approach. We determine the optimal anchor placement pattern for increased accuracy and how to achieve a particular accuracy goal with the least anchor count. Our analytical results are further validated through simulation.