A Scalable Protocol for Cooperative Time Synchronization Using Spatial Averaging

TL;DR

This paper introduces a scalable protocol that employs spatial averaging to significantly reduce synchronization errors in large-scale, multi-hop sensor networks, enhancing overall timing accuracy.

Contribution

It proposes a novel spatial averaging protocol for sensor networks and provides analysis and simulations demonstrating improved synchronization accuracy.

Findings

Error variance decreases as 1/number of cooperating nodes

Spatial averaging reduces synchronization error accumulation

Simulation confirms improved performance over basic methods

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.