System and techniques for split-aperture beamforming

A sonar computing device, comprising:

• a processor;
• a detector array comprising a plurality of elements;
• and
• a memory storing a plurality of instructions, which, when executed on the processor, causes the sonar computing device to:
• receive, at two or more sets of two-dimensional (2D) subarrays of the detector array, raw data representing a three-dimensional (3D) volumetric view of a space, wherein a first set of 2D subarrays of the two or more sets of 2D subarrays includes elements of the detector array along a first direction and wherein a second set of 2D subarrays of the two or more sets of 2D subarrays includes elements of the detector array along a second direction;
• subdivide the raw data into a plurality of slices, each slice corresponding to raw data received at a given range from the detector array;
• beamform the raw data to obtain a plurality of beams;
• and
• correct resulting beamformed data of the beamforming by, for at least one of the plurality of data slices:
• obtaining first phase data from a first subset of the first set of 2D subarrays,
• obtaining second phase data from a second subset of the second set of 2D subarrays,
• correcting a beam position of each of the plurality of beams in the first direction and the second direction per voxel based on the first phase data and the second phase data, and
• interpolating the corrected beam position of each of the plurality of beams to an output grid.

One or more machine-readable storage media storing a plurality of instructions, which, when executed on a processor, causes a sonar computing device to:

• receive, at two or more sets of two-dimensional (2D) subarrays of a detector array comprising a plurality of elements, raw data representing a three-dimensional (3D) volumetric view of a space, wherein a first set of 2D subarrays of the two or more sets of 2D subarrays includes elements of the detector array along a first direction and wherein a second set of 2D subarrays of the two or more sets of 2D subarrays includes elements of the detector array along a second direction;
• subdivide the raw data into a plurality of slices, each slice corresponding to raw data received at a given range from the detector array;
• beamform the raw data to obtain a plurality of beams;
• and
• correct resulting beamformed data of the beamforming by, for at least one of the plurality of data slices:
• obtaining, by the sonar computing device, first phase data from a first subset of the first set of 2D subarrays,
• obtaining, by the sonar computing device, second phase data from a second subset of the second set of 2D subarrays,
• correcting, by the sonar computing device, a beam position of each of the plurality of beams in the first direction and the second direction per voxel based on the first phase data and the second phase data, and
• interpolating, by the sonar computing device, the corrected beam position of each of the plurality of beams to an output grid.