To address the limitations of underwater acoustic wave propagation, we propose a paradigm shift in how information is carried over short-range (tens of meters) acoustic links. We suggest the study -and then development- of a novel carrierless ultrasonic transmission and multiple access technique. Short, properly designed/shaped pulses are transmitted in the ultrasonic spectral regime following an adaptive time-hopping pattern with a superimposed adaptive spreading code. The effect is nearly seamless physical/MAC layer integration, potential for highest data rate communication by properly optimized spreading sequences, and LPD/LPI operation via low-power transmission. Analysis of the supported bit rates versus LPD/LPI performance characterization will be carried out as a function of range. Secondary -yet important- benefits of the proposed approach are low cost and weight oscillator-free transducers and excellent receiver interference suppressing capabilities along the well documented theory and practice of spread-spectrum signal reception. Net-Tune Technologies investigators (Dr. Tommaso Melodia and Dr. Dimitris Pados) are partnering with the State University of New York at Buffalo (academic institution subcontractor Prof. Stella Batalama) and Teledyne- Benthos (Chief Scientist Dale Green as consultant) to form a most experienced and qualified team to explore for the first time -to the very best of our knowledge- this new technical avenue toward 500Kbps or more communication across 100m or more underwater distances.
