The RAFOS System

Abstract

The RAFOS float is a small neutrally buoyant subsurface order, which, like its big brother the SOFAR float, uses the deep sound (or SOFAR) channel to determine its position as a function of time. Whereas the SOFAR float transmits to moored receivers, the ?12 kg glass pipe RAFOS float listens for accurately timed signals from moored sound sources to determine its position. The acoustic signal detection and norm of data are all handled by a CMOS microprocessor in the float. The data are recovered at the end of its mission when the float surface and telemeters its memory contents to Systeme Argos, a satellite-borne platform location and data collection system. Just a few sound sources provide navigation for an arbitrary number of floats.