Fourier-Domain Wavefield Rendering for Rapid Simulation of Synthetic Aperture Sonar Data

This paper introduces a new method for simulating synthetic aperture sonar (SAS) raw coherent echo data that is orders of magnitude faster than the commonly used point and facet diffraction models. The new approach uses Fourier wavefield generation and propagation in combination with a highly optimised optical rendering engine. It has been shown to produce a quantifiably similar quality of data and data products (i.e., images and spectra) to a point-diffraction model, capturing the important coherent wave physics (including diffraction, speckle, aspect-dependence, and layover) as well as effects of the SAS processing chain (including image focusing errors and artefacts). This new simulation capability may be an enabler for augmenting data sets with physically accurate and diverse synthetic data for robust machine learning.