—In this paper, we propose a collaborative localization scheme which utilizes, in addition to the range estimates to nodes with known locations (anchors), the range estimates between unlocalized nodes to estimate their positions. The proposed collaborative method is incorporated into the linear programming (LP) framework proposed in [13] and is implemented in a distributed fashion. We also adopt a constrained nonlinear optimization method to deal with the degenerate cases in the LP approach, i.e., when an unlocalized node has less than three line-of-sight (LOS) range estimates to localized nodes. Simulation results suggest that this collaborative quasi-LP framework can improve the localization accuracy as well as increase the percentage of nodes that are able to be localized, as compared to the standard sequential least-squares (LS) estimator.
Tao Jia, R. Michael Buehrer