Comments: pdf
Ref.: INCREASE'2025, July 2025
Abstract:
Underwater imaging plays an essential role in environmental monitoring and exploration but
remains challenging due to the limitations of optical systems in low-light conditions.
Imaging sonar provides better performance in such environments and over longer distances;
however, state-of-the-art systems often rely on complex hardware configurations, increasing
cost and energy consumption. This work investigates a novel sonar imaging approach based on
spiral acoustic sources, which allow direction-of-departure estimation using minimal hardware
in a monostatic setup. By analyzing the departure azimuth of reflected acoustic paths, it is
possible to estimate the locations of reflection points and reconstruct 2D images of the
environment. An acoustic propagation model (APM) for 3D environments was developed to validate
this concept and was experimentally tested in a controlled pool environment. The proposed system
successfully detected sections of the pool walls, validating the spiral field-based imaging system,
but with some limitations. These promising results support the potential of spiral acoustic sources
for low-cost and sustainable underwater sonar imaging systems.