Acoustic imaging by three-dimensional acoustic Luneburg meta-lens with lattice columns

Underwater imaging with a moving acoustic lens

The acoustic lens is a high-resolution, forward-looking sonar for three dimensional (3-D) underwater imaging. We discuss processing the lens data for recreating and visualizing the scene. Acoustical imaging, compared to optical imaging, is sparse and low resolution. To achieve higher resolution, we obtain a denser sample by mounting the lens on a moving platform and passing over the scene. This...

Three-dimensional Acoustic Source Mapping

When beamforming is applied for acoustic source mapping, the sound pressure contributions of any sound sources are most often mapped to a planar or a surface map. However, some practical applications would benefit from a three-dimensional mapping, where the map consists of a three-dimensional grid. It is shown that the extension of microphone array beamforming techniques to three-dimensional ma...

Three-Dimensional Virtual Acoustic Displays

Three-dimensional digital beamforming for near-field wideband acoustic imaging

To generate volumetric acoustic images, a planar array of sensors is required to collect the signals coming from a 3-D scene. The method most frequently used to process the acquired signals is a digital beamforming algorithm. In general, due to the high number of sensors and beam signals, the computational load is prohibitive for real-time image generation. In this paper, the options for a freq...

Chirp zeta transform beamforming for three-dimensional acoustic imaging.

This letter considers the possibility of the generation of three-dimensional acoustic images with a limited computational load by considering the extension of Chirp zeta transform beam forming to the case of planar array and near-field conditions. This extension, with a few innovative solutions, allows for a dramatic reduction in the number of on-line operations over traditional time-domain bea...