Real-time clock synchronisation in underwater acoustic networks

This paper proposes an algorithm for real-time clock synchronisation in underwater acoustic networks. The algorithm models modem clocks as linear functions and embeds the data necessary for the clock synchronisation procedure as time stamps that can be communicated in the payload of later messages and only when necessary, hence limiting the communication overhead. The proposed solution takes explicitly into account the limitations of the acoustic communication channel and network node mobility. Specific implementation issues are discussed for its deployment within operational networks. Experimental results are given from the COLLAB-NGAS14 campaign, held in October 2014 off the coast of West Italy.