Small element array algorithm for correcting phase aberration using near-field signal redundancy. I. Principles.

Area of Science:

• Array signal processing
• Near-field acoustics
• Phase aberration measurement

Background:

• Previous algorithms were designed for large element arrays, limiting their application.
• Measuring phase aberrations is crucial for accurate imaging and signal focusing.

Purpose of the Study:

• To propose a novel near-field signal-redundancy algorithm for small element arrays.
• To enable the measurement of angle-dependent phase-aberration profiles.
• To analyze and compare methods for dynamic near-field delay correction.

Main Methods:

• Forming subarrays of adjacent elements to narrow beams.
• Collecting common midpoint signals with steered beams.
• Analyzing signal similarity using the corresponding-signal concept.

Main Results:

• The proposed algorithm effectively measures angle-dependent phase aberrations in small element arrays.
• Subarray formation allows for beam narrowing and steering, crucial for detailed profiling.
• Analysis of delay correction methods provides insights into signal similarity.

Conclusions:

• The developed algorithm extends phase aberration measurement to small element arrays.
• The corresponding-signal concept offers a valid framework for analyzing delay correction methods.
• This work advances near-field measurement techniques for diverse signal processing applications.