Techniques for phase correction in coherent ultrasound imaging systems

Area of Science:

• Wave optics
• Signal processing
• Array antenna theory

Background:

• Phase aberrations significantly degrade imaging quality in near-field applications.
• Accurate phase correction is crucial for reconstructing high-resolution images.
• Existing methods like the neighbor element technique have limitations in performance.

Purpose of the Study:

• To introduce and evaluate three new phase aberration correction techniques.
• To compare the efficacy of these novel methods against the classical neighbor element technique.
• To assess the performance using point-spread function simulations for various targets.

Main Methods:

• Development of three distinct phase aberration correction algorithms: central element, variable speckle look-back, and variable central speckle look-back.
• Simulation of the point-spread function (PSF) for both point and speckle targets.
• Quantitative comparison of the accuracy of the new techniques against the neighbor element method.

Main Results:

• The central element technique aligns echo-signals with the central array element.
• Variable speckle look-back aligns signals with the sum of previously corrected elements.
• Variable central speckle look-back aligns signals with the central group of previously corrected elements.
• Simulations indicate superior accuracy of the proposed techniques over the neighbor element method.

Conclusions:

• The developed central element, variable speckle look-back, and variable central speckle look-back techniques offer improved phase aberration correction.
• These novel methods provide enhanced accuracy for near-field imaging applications.
• The findings suggest a significant advancement over conventional phase correction strategies.