Fully distributed clock synchronization in wireless sensor networks under exponential delays

In this paper, we study the global clock synchronization problem for wireless sensor networks under unknown exponential delays in the two-way message exchange mechanism. The joint maximum likelihood estimator of clock offsets, clock skews and fixed delays for the network is formulated as a linear programming (LP) problem. Then, based on the alternating direction method of multipliers (ADMM), we propose a fully distributed synchronization algorithm which has low communication overhead and computation cost. Simulation results show that the proposed algorithm achieves better accuracy than consensus algorithm and the distributed least squares algorithm, and can always converge to the centralized optimal solution. HighlightsNetwork-wide clock synchronization problem under exponential message delays is solved.The problem is cast into a linear programming problem.ADMM is exploited to obtain a fully-distributed algorithm.Closed-from expressions are available for each update step in the algorithm.The proposed algorithm is guaranteed to converge to the global optimal solution.

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