Advanced Physics-Based Modeling of Discrete Clutter and Diffuse Reverberation in the Littoral Environment

Abstract

Abstract : ELECTRONIC FILE CHARACTERISTICS: 34 files; Adobe Acrobat (.PDF), MS Word (.DOC), MS PowerPoint (.PPT) and video files (.AVI,.WAV). PHYSICAL DESCRIPTION: 1 CD-ROM; 4 3/4 in.; 28.0 MB. ABSTRACT: In response to the Navy STTR Topic N03-T011, Physics-based modeling of Acoustic Reverberation in the Littoral Environment, a team representing PSI (Planning Systems Inc.), ARL-PSU (Applied Research Laboratory - Penn State University) and NRL-DC (Naval Research Laboratory - District of Columbia) was assembled to develop a broadband time series simulation capability for both discrete clutter and diffuse reverberation. This simulation capability is based upon the work by Kevin LePage (NRL-DC), who is participating on this STTR as an outside funded resource, and uses the coherent summation of narrow band results using normal mode methods to generate the broadband time series simulations. This high level of simulation fidelity is proposed for use in the LAMP (Littoral ASW Multistatics Program) and AEER (Advanced Extended Echo Ranging) programs as a tool for active, coherent sonar system development. The product of the Phase II STTR will not replace an existing modeling capability within the proposed programs but rather will provide these programs with an entirely new simulation capability. Current modeling tools at low and mid-frequencies (up to 5 kHz), including the Navy standard ASPM (Acoustic System Performance Model) and CASS (Comprehensive Acoustic System Simulation) models, cannot produce a simulated time series or simulate the effect of discrete clutter at the receiver. The simulation tool being developed under this Phase II STTR is intended to augment the in-water testing done on active, coherent sonar systems and will allow more sophisticated in-water testing through the use of simulation during the early design process.