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arXiv · 2610.15823

Acoustic Scattered Field Calculation for a Moving Source Using Time-Dependent Physical Optics

Asaf Kor·Gal Ben Yelid·Amir Boag·Lea Beilkin-Sirota
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Abstract

We present a time-dependent physical optics (TDPO) formulation for computing the acoustic scattered field of a stationary object in response to a moving source in three-dimensional space. Due to the motion of the source, which may be fast, the conventional frequency-domain PO method is not employed. Instead, a time-domain variant that explicitly accounts for the motion is formulated. The study focuses on the near-field regime, where source motion induces a complex wave field beyond a simple Doppler effect. The proposed algorithm accommodates arbitrary source trajectories and arbitrary signal bandwidth, as well as high source velocities relative to the speed of sound. Near and beyond the shadow boundary, where PO is least accurate, the formulation is supplemented by a Fock correction of the surface field, extended here to a moving source with a harmonic signal. The method matches or exceeds the accuracy of finite element simulations at a computational cost lower by orders of magnitude.

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Asaf Kor, Gal Ben Yelid, Amir Boag, Lea Beilkin-Sirota. 2026-10-11. Acoustic Scattered Field Calculation for a Moving Source Using Time-Dependent Physical Optics. https://arxiv.org/abs/2610.15823

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