Increasing circular synthetic aperture sonar resolution via adapted wave atoms deconvolution

Area of Science:

• Oceanography
• Acoustic Imaging
• Signal Processing

Background:

• Circular Synthetic Aperture Sonar (CSAS) offers high-resolution sonar imaging by maximizing aperture length.
• Back-projection algorithms in CSAS reconstruction create impulse response asymmetry as imaged points move from the acquisition circle's center.

Purpose of the Study:

• To propose a new sampling scheme for CSAS image reconstruction that ensures a uniform point spread function (PSF) across the entire field of view.
• To analytically derive closed-form solutions for the CSAS PSF in both image and Fourier domains.
• To develop and apply an adapted atom waves basis for CSAS image decomposition and deconvolution.

Main Methods:

• A novel sampling scheme for CSAS image reconstruction is proposed, enabling each point to act as a virtual CSAS acquisition center.
• Analytical derivation of closed-form solutions for the CSAS PSF in image and Fourier domains.
• Application of atom wave deconvolution using an adapted basis to simulated CSAS data.

Main Results:

• The proposed sampling scheme results in a uniform PSF for the entire CSAS image.
• Closed-form solutions for the CSAS PSF were successfully derived.
• Atom wave deconvolution improved image resolution by reducing PSF energy leakage in simulated data.

Conclusions:

• The developed sampling scheme effectively addresses the dissymmetry issue in CSAS image reconstruction.
• Understanding the CSAS PSF facilitates the development of advanced image decomposition techniques.
• Atom wave deconvolution shows promise for enhancing resolution in CSAS imaging.