Improved multi-hop time synchronization for Underwater Acoustic Networks

摘要: Time synchronization is important for many distributed applications in Underwater Acoustic Networks (UANs) with large propagation delay, such as precise scheduling, target tracking and energy conservation. In this paper, we prove that the accuracy of time skew estimation increases number overheard packet exchange from other neighboring nodes increases, propose a light-weighted algorithm multi-hop UANS, named Improved Multi-hop Synchronization Networks(IMSUAN). IMSUAN consists three parts. The first one to establish tree reference node root, assign each level low possible. second synchronize parent by dedicated three-time handshake overhear packets nodes. third filter inaccurate time-stamps packets. simulation platform OPNET evaluate performance IMSUAN. Simulation results show extended Tri-message, MSUAN are same when no overhearing exists. However, possible random topology, can be 60% better than Tri-Message 40% MSUAN.