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A Scalable Protocol for Cooperative Time Synchronization Using Spatial Averaging

An-swol Hu·Sergio D. Servetto
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Abstract

Time synchronization is an important aspect of sensor network operation. However, it is well known that synchronization error accumulates over multiple hops. This presents a challenge for large-scale, multi-hop sensor networks with a large number of nodes distributed over wide areas. In this work, we present a protocol that uses spatial averaging to reduce error accumulation in large-scale networks. We provide an analysis to quantify the synchronization improvement achieved using spatial averaging and find that in a basic cooperative network, the skew and offset variance decrease approximately as $1/\bar{N}$ where $\bar{N}$ is the number of cooperating nodes. For general networks, simulation results and a comparison to basic cooperative network results are used to illustrate the improvement in synchronization performance.

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An-swol Hu, Sergio D. Servetto. 2006-11-01. A Scalable Protocol for Cooperative Time Synchronization Using Spatial Averaging. https://arxiv.org/abs/cs/0611003

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