Theoretical and experimental study on multibeam synthetic aperture sonar

Area of Science:

• Underwater acoustics
• Sonar imaging technology
• High-resolution acoustic detection

Background:

• Underwater acoustic imaging is crucial for small-target detection.
• Conventional systems like multibeam echo sounders (MBESs) and synthetic aperture sonar (SAS) have limitations such as decreasing resolution with distance and data gaps.
• These limitations hinder the quality of underwater acoustic images.

Purpose of the Study:

• To introduce a novel two dimensional multibeam synthetic aperture sonar (MBSAS) model.
• To overcome the resolution and gap limitations of conventional underwater imaging instruments.
• To achieve high-resolution, gap-free three dimensional (3D) acoustic imaging.

Main Methods:

• Design of a two dimensional multibeam synthetic aperture sonar (MBSAS) model.
• Development of an echo model and transducer array manifold for engineering applications.
• Validation through imaging theory, target simulations, and a tank experiment.

Main Results:

• The MBSAS model successfully produced a detailed 3D full-scan acoustic image in a tank experiment.
• The obtained images clearly indicated target shapes and could separate adjacent targets.
• Simulations and experimental results demonstrated superior performance compared to conventional MBES and SAS systems, with better energy focusing.

Conclusions:

• The proposed MBSAS model is feasible and effective for high-resolution underwater acoustic imaging.
• MBSAS provides a significant advancement over existing technologies for detailed 3D imaging and small-target detection.
• The system offers improved image quality, gap-free coverage, and enhanced energy focusing capabilities.