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Finite difference time domain ray-based modelling of acoustic scattering for target identification and tracking

The Finite Difference Time Domain (FDTD) method has provided a powerful technique for modelling and simulation of solutions of a variety of acoustics problems. The purpose of this investigation is to present work on the development of time-domain models of acoustic scattering from targets near a flat pressure-release boundary for use in identification and tracking from a moving receiving platform. The timing from acoustic source to reception are dependent on the location dependent sound speed profile and the specular scattering points on the target. There can be multiple specular points revealed on the target because of interactions with the flat boundary; each of which are modelled utilizing the FDTD method providing path corrections due to variation in propagation brought on by the sound speed profile of the environment.