Phase Coherent Acoustic Telemetry Development

This research and development project will investigate the feasibility of data communication with submerged instruments using phase-coherent acoustic telemetry. We will conduct a series of pilot experiment, to determine an efficient modulation method for underwater acoustic data transmission. These experiments will center around real-time data transmission using a variety of promising modulation/coding methods. The experiment sites have been selected to match configurations where real-time data telemetry from remote ADCPe is of interest. The transmitted data will be recorded and processed off-line to determine optimal receiver structures and compare the merit, of a number of signaling methods. The reeults will be ueed to make a preliminary design of a prototype phase-coherent modem suitable for vertical telemetry in deep water, and to evaluate the feasibility of phase- coherent telemetry for communication in the highly reverberant shallow-water enviroruDent over medium ranges of a few kilometers.