AN EXPERIMENT IN SUB-SEA NETWORKS - THE LOTUS SEA TRIALS

摘要

This paper describes a set of sea trials, held the summer of 1999, as part of the MAST funded LOTUS project. The main objective of this project was to develop a method of communicating with a number of sub-sea units, deployed over a wide area of the sea-bed, without the need for cables. The trials involved the daily deployment and recovery of two, sea-bed mounted, battery driven transmission units, which sent signals to a single, multielement receiver. The receiver remained on the sea-bed for the whole of the trial period, being linked each day to one of two support vessels. The signals were designed such that packets were transmitted both individually by each unit, as well as having periods when both transmitters were operating simultaneously. Various coding schemes were employed in order to facilitate detection of each "user" during dual transmissions. The geometry of the receiver also allowed for both vertical and horizontal discrimination.