LONG-TERM GOALS Our goal is to develop and demonstrate a low-cost system for retrieving oceanographic data from instruments in the coastal ocean and delivering these data in near real time. This work is conducted under the National Ocean Partnership Program with Federal, State, Academic and private industry participation and funding. OBJECTIVES We wish to develop and demonstrate a low-cost modular system for telemetering oceanographic data ashore. The system consists of 4 components: (1) a

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... ost, medium bandwidth acoustic data link from oceanographic instruments below the surface to a surface buoy; (2) an acoustic modem/RF link to receive the acoustic transmissions and telemeter data to shore; (3) a buoy system for deployment of the acoustic modem/RF link, and (4) a system for distributing the data over the World Wide Web. APPROACH Our conceptual approach is to use very low cost, low power acoustic transmitters which are capable of transmitting data from many sensors located on a mooring line or on the bottom in the vicinity of a surface buoy (figure 1). These acoustic transmitters are small, inexpensive, and low power, except during the brief periods during which they burst data at 2000 -4000 b/s. They operate in the 30-40 kHz band in a random access mode. The receive system, located at the surface buoy, consists of a Utility Acoustic Modem integrated directly with an RF telemetry link capable of providing high-reliability, medium bandwidth connection to shore. In this work a line-of-sight RF link, capable of operating over