Accession Number:

ADA574863

Title:

Closed-form and Numerical Reverberation and Propagation: Inclusion of Convergence Effects

Descriptive Note:

Annual rept.

Corporate Author:

CENTRE FOR MARITIME RESEARCH AND EXPERIMENTATION LA SPEZIA (ITALY)

Personal Author(s):

Report Date:

2012-09-30

Pagination or Media Count:

6.0

Abstract:

The flux formulation of propagation has been used to calculate reverberation, target echo, and signal excess very efficiently in a model developed by Harrison called Artemis. This model is used in the operational planning aid MSTPA at CMRE. Propagation in this formulation falls off monotonically with range. The goal of the ONR-funded work is to improve the propagation accuracy by including convergence and focusing effects without compromising the simplicity and efficiency of the approach. The objective has been to write out the theory, i.e. start with the modulus-square of the coherent mode sum and reject rapidly oscillating terms to leave fluctuations on a scale of a ray cycle distance. These formulations were to be evaluated in Matlab and compared with each other and with runs of other well-established models, in this case the normal mode model Orca.

Subject Categories:

  • Numerical Mathematics
  • Acoustics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE