Paul C. Etter
P.O. Box 5622, Rockville, MD 20855-5622
Results from a survey of recent developments in Naval underwater acoustic modeling are compared with those of two previous surveys conducted at 8-year intervals [P. C. Etter and R. S. Flum, Sr., J. Acoust. Soc. Am. Suppl. 1 65, S42 (1979); P. C. Etter, J. Acoust. Soc. Am. Suppl. 1 82, S102 (1987)]. All surveys cover basic acoustic models and sonar performance models. Basic acoustic models include propagation, noise, and reverberation models. Sonar performance models integrate basic acoustic models, signal processing models and supporting databases into cohesive operating systems organized to solve the active or passive sonar equations [P. C. Etter, Underwater Acoustic Modeling (Elsevier, Amsterdam, 1991); 2nd ed. (Chapman & Hall, 1995)]. Summary tables identify and highlight noteworthy characteristics of 83 propagation models, 15 noise models, 14 reverberation models, and 14 sonar performance models. These surveys provide a retrospective view of modeling developments over the past two decades and document a 160% increase in the number of models that are now available for applications in sonar technology. This updated baseline also suggests future directions for Naval modeling in an era of defense conversion including new applications in oceanographic research.