Improving Indoor Positioning Accuracy with Dense, Cooperating Beacons

We improve indoor positioning location accuracy by opportunistically enlisting wireless client devices to temporarily serve as unmanaged beacons (or access points). A two-phase positioning scheme is proposed; in the initial phase, a target node and its neighbors are located using managed APs with known locations. In the second phase, the target node's position is refined by neighbor nodes with uncertain locations serving as short-range wireless beacons themselves. Through simulations and analysis we explore the geographic conditions and noise models under which exploiting the availability of unmanaged beacons can improve location accuracy. We argue that as the spatial density of wireless devices grows, it is increasingly desirable to call on a preferred subset of neighbor nodes with uncorrelated anchor errors to serve as beacons to improve location accuracy.