beam tunneling

Perhaps the most widely known scientific contribution of the Centre is the development of several underwater acoustic numerical models.  Acoustic models provide the means for assimilating information on the ocean environment and on acoustic propagation, reverberation and noise, in a form in which it can be readily accessed and applied for sonar research, engineering and operational use as a software library or as a full package.

The Centre either developed models from the scratch or significantly modified existing ones written at other NATO national research laboratories. This was (and still is) a common practice at the CMRE's research community as its backbone is formed by NATO national scientists who are in temporary contracts/assignments.  The outcome is a fluid knowledge transfer between the Centre and the nations for their mutual benefit.

The peak period of the development of acoustic models at the Centre was the decade of the 90's. Plenty of publications - either laboratory reports or open literature works such as journal articles or conference papers - put the former SACLANTCEN on the map of the world's physics community, whereas most of its former output had been little known outside the NATO national research laboratories due to security classification caveats.

Some noted underwater acoustic propagation models developed on the 90s were SAFARI, KRAKEN, C-SNAP, PROSIM, PAREQ, BELLHOP, SNAP-RD. Other acoustic models focused on acoustic reverberation (B-STAR, C-SNAP-REV, PAREQ-REV), acoustic inversion (SAGA), or target scattering (FAWCETT, BORIS).

The Centre will be indebted to scientists like Finn B. Jensen, Carlo M. Ferla, Michael B. Porter, John A. Fawcett, William A. Kuperman, Hendrick Schmidt, Kevin LePage, Peter Nielsen,  Eric Pouliquen, Peter Gerstoft, Chris H. Harrison and many others for their contributions to acoustic modelling. 

The next decade would see many new contributions (either by the same or other scientists) which will merit their own story.


Acoustic transmission loss

Some references:

Jensen, Finn B. [et al.] , eds . Computational ocean acoustics. 2nd ed. New York: Springer, 2011.

Diachok, O. [et al.], eds. Full field inversion methods in ocean and seismo-acoustics. Dordrecht: Kluwer, 1995.

Ellis, Dale D.; Preston, John R.; Urban, Heinz G., eds. Ocean reverberation. Dordrecht: Kluwer, 1993.

Urban, Heinz G. Adaptive methods in underwater acoustics [NATO Advanced Study Institute on Adaptive Methods in Underwater Acoustics]. Dordrecht: Reidel, 1985.

Jensen, Finn B. ; Ferla, Carlo M. Numerical solutions of range-dependent benchmark problems in ocean acoustics. In: Journal of the Acoustical Society of America, vol. 87, pp. 1499-1510 (1990).

Porter, Michael B. The time-marched FFP for modelling acoustic pulse propagation. In: Journal of the Acoustical Society of America, vol. 87, pp. 2013-2023 (1990).

Porter, Michael B. ; Bucker, H. P. Gaussian beam tracing for computing ocean acoustic fields. In: Journal of the Acoustical Society of America, vol. 82, pp. 1349-1359 (1987).

Schneider, Hans G. Acoustic models at SACLANTCEN. La Spezia: NATO SACLANTCEN, 1995. Report SM-285.

Ferla, Carlo M. ; Porter, Michael B. ; Jensen, Finn B. C-SNAP: Coupled SACLANTCEN Normal mode propagation loss model. La Spezia: NATO SACLANTCEN, 1993. Report SM-274.

Porter, Michael B. The KRAKEN normal mode program. La Spezia: NATO SACLANTCEN, 1991. Report SM-245.