This award will support hardware and software upgrades for sonar systems used on deep-submergence vehicles. The present collection of >10 units used in processing will be replaced by an off-the- shelf workstation, decoder and standard digital signal processor boards. Software will be developed to produce user-friendly output, and to simply processing so that trained engineers are not required. Finally, software will be developed to make data compatible for other computer tool systems (MB and GMT), eventually allowing interactive processing and display by users of IBM- and Macintosh-compatible systems.