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arXiv · 1202.0022

Time-varying Clock Offset Estimation in Two-way Timing Message Exchange in Wireless Sensor Networks Using Factor Graphs

Aitzaz Ahmad·Davide Zennaro·Erchin Serpedin·Lorenzo Vangelista
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Abstract

The problem of clock offset estimation in a two-way timing exchange regime is considered when the likelihood function of the observation time stamps is exponentially distributed. In order to capture the imperfections in node oscillators, which render a time-varying nature to the clock offset, a novel Bayesian approach to the clock offset estimation is proposed using a factor graph representation of the posterior density. Message passing using the max-product algorithm yields a closed form expression for the Bayesian inference problem.

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Aitzaz Ahmad, Davide Zennaro, Erchin Serpedin, Lorenzo Vangelista. 2012-01-31. Time-varying Clock Offset Estimation in Two-way Timing Message Exchange in Wireless Sensor Networks Using Factor Graphs. https://arxiv.org/abs/1202.0022

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