The Weston Memorial workshop: progress to date on low frequency active sonar scenarios

Abstract

The need for benchmarks of propagation loss was addressed in a series of propagation workshops in the 1980s. These workshops resulted in a set of well defined propagation scenarios and a corresponding set of benchmark solutions. Within the context of sonar performance modelling, these benchmarks provide a valuable means of testing one-way propagation models, and thereby help build confidence in passive sonar performance prediction tools. In the context of active sonar performance prediction models, the need for benchmark solutions remains today. Validated models of echo and reverberation are still in their infancy for low frequency active sonar (LFAS). The issue of reverberation modelling was addressed by two workshops sponsored by the US Office of Naval Research (ONR), and held at the Applied Research Laboratory, University of Texas at Austin in November 2006 and May 2008. The Weston Memorial or "Validation of Sonar Performance Assessment Tools" workshop, held at the University of Cambridge in April 2010, built on the ONR reverberation scenarios by adding ambient noise, and including signal processing as far as the signal to noise ratio after beamforming and matched filtering. Particular attention is given to the influence on sonar performance of the 3D nature of the bathymetry.